A course of english for students of agricultural engineering

TABLE OF CONTENTS Page Part I: Electrical and Mechanical Engineering Unit 1: Engineering – What’s it all about?. What kinds of engineers are concerned with these areas – electrical, me

MINISTRY OF EDUCATION AND TRAINING HUE COLLEGE OF AGRICULTURE AND FORESTRY

LỜI MỞ ĐẦU

“A course of English for students of agricultural engineering” là giáo trình tiếng Anh

chuyên ngành cĩ thể dùng làm tài liệu giảng dạy hoặc tài liệu tham khảo cho sinh viên ngành cơ điện nơng nghiệp, ngành kỹ thuật cơ khí nơng nghiệp của trường Đại Học Nơng Lâm và Đại Học Sư Phạm (ngành kỹ thuật)

Giáo trình này được biên soạn trên cơ sở sinh viên đã học qua chương trình tiếng Anh cơ bản; cĩ vốn kiến thức cơ bản về ngữ pháp tiếng Anh và kiến thức cơ bản

về các chuyên ngành liên quan đến cơ điện; sinh viên cĩ nhu cầu phát triển kỹ năng đọc, viết và dịch tiếng Anh chuyên ngành cơ điện nơng nghiệp Do đĩ mục đích của giáo trình là:

Giúp sinh viên làm quen với văn phong tiếng Anh khoa học kỹ thuật

Rèn luyện kỹ năng đọc hiểu các văn bản khoa học

Cung cấp cho sinh viên các từ, thuật ngữ chuyên ngành

Luyện thực hành viết và dịch một số cấu trúc ngữ pháp thường gặp

Với đối tượng của giáo trình là sinh viên năm thứ 3 trường Đại Học Nơng Lâm Huế và thời lượng dành cho mơn học là 60 tiết (4 đơn vị học trình), giáo trình này gồm 10 units và một số bài đọc thêm Các bài text được trích dẫn hoặc phỏng theo các tài liệu khoa học nhằm đảm bảo tính xã thực của văn bản Các bài tập ngữ pháp được biên soạn theo ngữ pháp tiếng Anh cơ bản và kết hợp các kiến thức chuyên ngành cơ điện

cơ bản mà sinh viên đã được học

Việc biên soạn giáo trình này chắc chắn khơng tránh khỏi những khiếm khuyết Chúng tơi mong nhận được gĩp ý xây dựng của độc giả và người học để giáo trình ngày càng hồn thiện hơn

Lê Thị Thanh Chi

TABLE OF CONTENTS

Page

Part I: Electrical and Mechanical Engineering

Unit 1: Engineering – What’s it all about ? ………

Unit 2: Engineering Materials ………

Unit 3: Mechanisms ………

Unit 4: Forces in Engineering ………

Unit 5: The Electric Motor ………

Part II: The Agricultural Machinery Unit 6: The Agricultural Tractor ………

Unit 7: Tractor Engines ………

Unit 8: The Combine Harvester (A) ………

Unit 9: The Combine Harvester (B) ………

Unit 10: Farm Management ………

Further reading Portable Generator

Engine Classification

Connecting Rods and Crankshaft

The reel ………

Water Pumping System ………

Mechanization in Sugarcane Production – Development of seed cane planter ………

References …….4

…….10

…….15

…….24

…….31

…….39

…….50

…….59

…….69

…….77

PART I: ELECTRICAL AND MECHANICAL ENGINEERING

Engineering is largely a practical activity It is about putting ideas into action Civil

engineering is concerned with making bridges, roads, airports, etc Mechanical engineering deals with the design and manufacture of tools and machines Electrical engineering is about the generation and distribution of electricity and its many applications Electronic engineering

is concerned with developing components and equipment for communications, computing, and so on

Mechanical engineering includes marine, automobile, aeronautical, heating and ventilating, and others Electrical engineering includes electricity generating, electrical installation, lighting, etc Mining and medical engineering belong partly to mechanical and partly to electrical

2 Complete the blanks in this diagram using information from the text

3 Study these special words They show some of the areas in which engineers work

Can you identify them? What kinds of engineers are concerned with these areas – electrical, mechanical or both?

Beer brewery – planes - super highway – blocks of building – X ray machine

Now read the following texts to check your answer Match each text to one of the word

or phrase above

Transport: cars, trains, ships and planes are all products of mechanical engineering Mechanical engineers are also involved in support services such as roads, rail track, harbours and bridges

Food processing: Mechanical engineers design, develop and make the machines and the

the supermarket

Medical engineering: Body scanners, X-ray machines, life-support systems, and other high-tech equipment result from mechanical and electrical engineers combining with medical experts to convert ideas into life-saving and preserving products

Building services: Electrical engineers provide all the services we need in our homes and places of work, including lighting, heating, ventilation, air-conditioning, refrigeration, and lifts

Energy and power: Electrical engineers are concerned with the production and distribution of electricity to homes, offices, industry, hospitals, colleges and schools, and the installation and maintenance of the equipment involved in these processes

(Source: Adapted from Turning Ideas into Action, Institution of Mechanical Engineers, and Engineering a career, Institution of Electronics and Electrical Incorporated Engineers)

4 When you read, it is important to have a clear purpose Here are some of the

purposes you may have for reading the texts Match one purpose to each kind of text

1 finding a job

2 pricing a component

3 finding out how to do something

4 choosing the best chapter to read

5 looking for specific information on a topic

6 learning about electrical equipment

In the United Kingdom you can …(1)… engineering at a college of further education or

a university Most college courses …(2)… from one to two years University undergraduate course …(3)… engineering last from three to four years

A college will take …(4)… after four years of secondary school education Most students study full-time, …(5)… day-release courses are available for people who …(6)… in local engineering companies Students will be given a certificate …(7)… a diploma at the

…(8)… of their course

Most university students will have completed six …(9)… of secondary school Others will have taken a diploma course at college …(10)… give degrees A Bachelor‟s degree

…(11)… three to four years A Master‟s …(12)… requires a further year

Students / degree / last / years / in / work / end / study / universities / or / but (although) / takes

B Language study: deals with / is concerned with

What is the link between column A and column B ?

1 Mechanical engineering deals with machines

2 Mechanical engineers deal with machines

3 Mechanical engineering is concerned with machines

4 Mechanical engineers are concerned with machines

5 Machines are the concern of mechanical engineers

Match each item in column A with an appropriate item from column B and link the two

d cables and switch-gear

e communication and equipment

f ships

g planes

h cars and trucks

i power stations

C Word study: Word stress

Words are divided into syllables For example:

Look at these words Try to mark the stressed syllable

New words and expressions:

sự phát điện

sự phân phối điện năng (thuộc về) hàng hải (thuộc) ngành hàng không sưởi và thông gió

chế biến thực phẩm thu hoạch

bảo quản bảo dưỡng, bảo trì (máy móc) trạm điện năng

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LANGUAGE IN FOCUS Using adverb clauses to show time relationships:

after (a)After she graduates, she will get a job

(b) After she (had) graduated, she got a job

A present tense, not a future

tense is used in an adverb clause of time Notice example (b) and (d)

before (c) I will leave before he comes

(d) I (had) left before he came

when (e) When I arrived, he was talking on the phone

(f) When I got there, he had already left

(g) When it began to rain, I stood under a tree

(h) When I was in Chicago, I visited the museum

(i) When I see him tomorrow, I will ask him

When = at that time (notice the different time relationship expressed by the tenses)

While

As

(j) While I was walking home, it began to rain

(k) As I was walking home, it began to rain

While, as = during that time

By the time (l) By the time he arrived, we had already left

(m) By the time he comes, we will already have left

By the time = one event is completed before another event (notice the use of the

past perfect and future perfect

in the main clause)

Since (n) I haven‟t seen him since he left this morning Since = from that time to the

present (Notice the present perfect is used in the main clause)

Until

till

(o) We stayed there until we finished our work

(p) We stayed there till we finished our work

Until, till = to that time and then no longer (till is used primarily in speaking rather than writing)

As soon as

Once

(q) As soon as it stops raining, we will leave

(r) Once it stops raining, we will leave

As soon as, once = when one event happens, another event happens soon afterwards

As long as

So long as

(s) I will never speak to him again as long as I live

(t) I will never speak to him again so long as I live

As soon as, so long as = during all that time, from beginning to end

Whenever

Every time

(u) Whenever I see her, I say hello

(v) Every time I see her, I say hello

Whenever = every time

The first time

The last time

The next time

(w) The first time I went to New York, I went to an

opera

(x) I saw two plays the last time I went to New York

(y) The next time I go to New York, I‟m going to see

a ballet

Adverb clauses can be introduced by the following: first

The second time third

last next

PRACTICE

A Complete the following Pay attention to verb tenses

1 Last night I went to bed after I _ my homework

2 Tonight I will go to bed after I my homework

3 Ever since I was a child, I _ afraid of dogs

4 Jane‟s contact lens popped out while she basketball

5 Be sure to reread your composition for errors before you it in to the

teacher tomorrow

6 By the time I left my apartment this morning, the mail carrier _ the mail

7 I have known Jim Bates since he _ ten years old

8 A black cat ran across the road as I my car to work this morning

9 By the time I leave this city, I _ here for four months

10 Whenever Mark angry, his nose gets red

11 I to the beach whenever the weather was fine, but now I don‟t have

time to do that because I have to study

13 The next time I _ to Hawaii, I‟m going to visit Mauna Loa, the world largest volcano

14 I had fried chicken the last time I _ at that restaurant

B Complete the following sentences Punctuate carefully Pay attention to verb tense usage

1 Just as I was falling asleep last night

2 I‟ll help you with your homework as soon as I

3 as long as I live 4 Just before I

5 The last time I

6 I had already when

7 Whenever

8 I will be here until I

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UNIT 2: ENGINEERING MATERIALS

A Reading: Scanning tables

In engineering, it is important to practice reading tables, charts, diagrams, and graphs because so much information is represented in these ways

Scanning is the best strategy for finding information in a table With scanning, you know before you read what sort of information you are searching for To scan a table, you move your eyes up and down the columns until you find the word or words you want To scan quickly, you must learn to ignore any information which will not help you with your task

1 Scan the table which follows to find a material which is:

f conductive and malleable

g durable and hard

h stiff and brittle

i ductile and corrosion-resistant

j heat-resistant and chemical-resistant

Materials Properties Uses

Copper Very malleable, tough & ductile,

highly conductive, resistant

corrosion-Electric wiring, PCBs, tubing

Brass (65% copper,

35% zinc)

Very corrosion-resistant Casts well, easily machined Can be work hardened Good conductor

Valves, taps, castings, ship fittings, electrical contacts

Mild steel (iron

with 0.15% to 0.3%

carbon)

High strength, ductile, tough, fairly malleable, cannot be hardened and tempered, low cost, poor corrosion resistance

Cutting tools such as drills, files, saws

Materials Properties Uses

Acrylic

Nylon

Stiff, hard, very durable, clear, can

be polished easily, can be formed easily

Hard, tough, wear-resistant, lubricating

self-Aircraft canopies, baths, double glazing

Bearings, gears, castings for power tools

heat-Adhesive, encapsulation of electronic components

Moulding, boat and car bodies

Electrical fitting, adhesives

2 Scan the table to find:

a A metal used to make aircraft

b Plastics used for adhesives

c Steel which can be hardened

d An alloy suitable for castings

e A plastic with very low friction

f A material suitable for safety helmets

g A metal suitable for a salt-water environment

h A metal for general construction use but which should be protected from corrosion

i A plastic for car bodies

j The metal used for the conductors in printed circuit boards

B Language study: 1 Making definitions

Study these facts from the table about aluminium:

1 Aluminium is a light metal

2 Aluminium is used to make aircraft

We can link these facts to make a definition of aluminium:

1+2 Aluminium is a light metal which is used to make aircraft

We can use the relative pronoun which in making definition of something, and the

which-clause is known as the adjective clause in these cases

Use the table above to make definitions of each of the materials in column A Choose the correct information in column B and C to describe the materials in column A

a allows heat or current to flow easily

b remains rigid at high temperatures

c does not allow heat or current to flow easily

d contains iron & 0.7% to 1.4% carbon

e becomes plastic when heated

f contains iron & 0.15% to 0.3% carbon

g formed by mixing other metals or elements

h consists of copper and zinc

2 Adding information to a text

Study this sentence about aluminium

Aluminium is used to make aircraft, engine components, and many items for the kitchen

We can add extra information to the sentence like this:

Aluminium, which is light, soft, and ductile, is used to make aircraft, engine components – for example, cylinder heads – and many items for the kitchen, such as

Add this extra information to the following text about plastics

1 Plastics can be moulded into plates, car components, and medical aids

2 Thermoplastics soften when heated again and again

3 Thermosetting plastics set hard and do not alter if heated again

4 ABS is used for safety helmets

5 Nylon is self-lubricating

6 Nylon is used for motorized drives in cameras

7 Acrylic is a clear thermoplastic

8 Acrylic is used for aircraft canopies and double glazing

9 Polyester resin is used for boat and car bodies

10 Polyester resin is hard and has good chemical and heat resistance

Plastics are synthetic materials They can be softened and moulded into useful articles They have many applications in engineering There are two types of plastics: thermoplastics and thermosetting plastics

ABS is a thermoplastic which is tough and durable Because it has high impact strength,

it has application where sudden loads may occur

Nylons is a hard, tough thermoplastic It is used where silent, low-friction operation is required

Acrylic can be formed in several ways It is hard, durable, and has many uses

Polyester resin is a thermosetting plastic used for castings It has a number of useful properties

C Word study: Properties of materials

Study these examples of adjective and noun pairs for describing the properties of materials

có tính dẫn điện bền

cứng và giòn, dễ gãy chống ăn mòn (kim loại) lực ma sát

môi trường nước mặn bảng điện

hợp kim

LANGUAGE IN FOCUS Using English to define

Aristotle suggested that a good definition should include the general classification of a term plus the specific characteristics that differentiate the term from other members of its class For

example, a definition of a giraffe should include a classification, such as, A giraffe is an animal, and specific characteristics, such as, A giraffe is tall, African animal with a very long neck

Definition formula:

Term = Class + characteristics

Example: Chemical energy is potential energy that is stored in gasoline, food, and oil

(Frequently, the characteristics appear as a relative clause beginning with which, that, who, or where)

Chemical energy = potential energy + that is stored in gasoline, food and oil

(term) (class) (characteristics)

Relative clauses:

A clause is a part of a sentence that contains a noun and a verb A relative clause is one that begins with which, that, where, or who Which and that are most commonly used in science definitions; who is used when referring to people Science definitions often include relative clauses containing the characteristics that distinguish an item from others in the class

Formulating definitions: Using the information given in each series, write a definition Use

the sentence patterns above to guide you

1 an amoeba / one-celled animal / constantly change its shape

An amoeba is a one-celled animal that constantly changes its shape

2 an antibiotic / drug / cures bacterial diseases

3 lung / organ / breathing

4 acoustics / science / sound

5 photosynthesis / process / plants manufacture food

6 catalyst / substance / speeds up but is not changed by a chemical reaction

7 calorie / unit / measures heat

8 cyclotron / apparatus / bombards the nuclei of atoms

Creating definitions: A good way to see if the definition is complete is to reverse it For

example, if we reverse an elephant is an animal, we get an animal is an elephant, and it is obvious that the definition for each of the following words and test each one by reversing it If you need help, use a dictionary

10 an aquarium

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UNIT 3: MECHANISMS

A Reading: Scanning a text

Scanning is the best strategy for searching for specific information in a text Move your eyes up and down the text until you find the word or words you want Try to ignore any information which will not help you with your task

1 Scan the text opposite quickly to find out which of these mechanisms are mentioned

1 cam 2 tap 3 pendulum 4 foot pump 5 Escalator

Mechanisms are an important part of everyday life They allow us to do simple things like switch on lights, turn taps, and open doors They also make it possible to use escalators and lifts, travel in cars and fly from continent to continent

Mechanisms play a vital role in industry While many industrial processes have electronic control systems, it is still mechanisms that deliver the power to do the work They provide the forces to press steel sheets into car body panels, to lift large components from place to place, to force plastic through dies to make pipes

All mechanisms involve some kind of motion The four basic kinds of motion are:

Rotary: Wheels, gears, and rollers involve rotary movement

Oscillating: The pendulum of a clock oscillates – it swings backwards and forwards Linear: The linear movement of a paper trimmer is used to cut the edge of the paper Reciprocating: The piston in a combustion engine reciprocates

Many mechanisms involve changing one kind of motion into another type For example, the reciprocating motion of a piston is changed into a rotary motion by the crankshaft, while a cam converts the rotary motion of the engine into the reciprocating motion to operate the valves

2 Now read the text to find the answer to these questions

1 What does a cam do?

2 What does oscillating mean?

3 How are plastic pipes formed?

4 What simple mechanisms in the home are mentioned directly or indirectly?

5 What is the function of the crankshaft?

6 Give an example of a device which can produce a linear movement?

7 How are car body panels formed?

8 What do mechanisms provide in industry?

B Language study:

1 Ways of linking ideas

When we write, we may have to describe, explain, argue, persuade, complain, etc in all these forms of writing, we use ideas To make our writing effective, we have to make sure our readers can follow our ideas One way of helping our readers is to make the links between the

ideas in our writing

What are the links between these pairs of ideas ? What words can we use to mark the links ?

1 Mechanisms are important to us

2 They allow us to travel

3 Mechanisms deliver the power to do work

4 They play a vital role in industry

5 Friction is sometimes a help

6 It is often a hindrance

Sentence 2 is a reason for sentence 1 We can link 1 and 2 like this:

Mechanisms are important to us because/since/as they allow us to travel

Sentence 4 is a result of sentence 3 We can link 3 and 4 like this:

Mechanisms deliver the power to do work so they play a vital role in industry

Mechanisms deliver the power to do work; therefore they play a vital role in industry

Sentence 6 contrasts with sentence 5 We can link 5 and 6 like this:

Friction is sometimes a help but it is often a hindrance

Show the links between these sets of ideas using appropriate linking words

1 Copper is highly conductive It is used for electric wiring

2 Weight is measured in newtons Mass is measured in kilogram

3 Nylon is used for bearings It is self-lubricating

4 ABS has high impact strength It is used for safety helmets

5 The foot pump is the class 2 lever The load is between the effort and the fulcrum

6 Friction is essential in brakes Friction is a nuisance in an engine

7 The upper surface of a beam is in compression The lower surface is in tension

8 Concrete beams have steel rods near the lower surface Concrete is weak in tension

2 Dealing with technical terms

One of the difficult things about the English of engineering is that there are many technical terms to learn Newer terms may be the same, or almost the same, in your own language But many terms will be quite different and you may not always remember them When this happens, you will have to use whatever English you know to make your meaning clear

The technical terms in column A are similar in meaning to the more general English in column B Match them

g swings backwards and forwards

h goes up and down

C Word study: Noun and Noun compounds

We can use adjectives to describe an object in greater detail For example:

a motor an electric motor

We can also use nouns For example:

Many relationships are possible in noun compounds For example:

an air motor a motor which uses air

carbon steel steel which contains carbon

titanium gears gears made of titanium

1 Put each of these examples in the correct column

1 carbon blocks 2 a power tool

3 aluminium alloy 4 a ball bearing

5 carbon fibre 6 a concrete beam

7 a gas burner 8 a diesel boat

9 roller bearings 10 a spring balance

11 a circuit board 12 a plastic tube

13 a plastic pipe 14 steel sheets

15 magnesium alloy

Uses is made of contains

……… ……… ………

………… ……… ………

………… ……… ………

………… ……… ………

………… ……… ………

………… ……… ………

………… ……… ………

………… ……… ………

2 What new relationships can you find in the example below? Rewrite each compound to

show the relationship For example:

a foot pump a pump which is operated by foot

a ribbon cable a cable which is like a ribbon

a gear lever a lever for operating gears

1 chain wheel 6 College lecturer

3 foot brake 8 Boiler thermostat

4 a hand throttle 9 Safety helmet

5 strain gauge 10 Aircraft engineer

New words and expressions:

hệ thống điều khiển bằng điện tử (chuyển động) dao động

(chuyển động) thẳng (chuyển động) tới lui chuyển động quay tấm thép

điểm tựa dầm làm bằng bê-tông thép không gỉ

cân lò xo đung đưa lui tới trở lực

tự bôi trơn

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LANGUAGE IN FOCUS

A Adjectives and adverbs

Look at these examples:

- Our vacation was too short – the time passed very quickly

- The driver of the car was seriously injured in the accident

Quickly and seriously are adverbs Many adverbs are made from an adjective + -ly:

Adjective: quick serious careful quiet heavy bad

Adverb: quickly seriously carefully quietly heavily badly

Not all words ending in –ly are adverbs Some adjectives end in –ly too, for example:

friendly lively elderly lonely silly lovely

B Adjective or adverb ?

* Adjectives (quickly/careful, etc.) tell us

about a noun We use adjectives before nouns

and after some verbs, especially be:

- Tom is a careful driver (not a

- Why do you always look so serious?

- She speak perfect English

* Adverbs (quickly/carefully, etc.) tell us about a verb An adverb tells us how somebody does

something or how something happens:

- Tom drove carefully along the narrow road (not drove careful)

- We didn‟t go out because it was raining heavily (not raining heavy)

- Please speak quietly (not speak quiet)

- I was disappointed that I did so badly on the test (not did so bad)

- Why don‟t you ever take me seriously?

- She speaks English perfectly

Compare these sentences with look:

Tom looked sad when I saw him (= he seemed sad; his expression was sad)

Tom looked at me sadly (= he looked at me in a sad way)

C Comparison

Look at these examples:

- Should I drive or take a train ? - You should drive It‟s cheaper

- Don‟t take the train It‟s more expensive

Cheaper and more expensive are comparative forms

After comparatives you can use than:

It‟s cheaper to drive than to take a train

Taking the train is more expensive than driving

The comparative form is –er or more

We use –er for short words (one syllable):

cheap –cheaper, fast – faster, large – larger

We also use –er for two syllable words that

end in –y (-y => -ier)

lucky – luckier, early – earlier, easy – easier,

pretty – prettier

- you‟re older than me

- The exam was easy – easier than we

expected

- Can you walk a little faster ?

- I‟d like to have a bigger car

- Last night I went to bed earlier than

usual

We use more for longer words (two syllables or more):

more serious, more often, more expensive

We use more for adverbs that end in –ly:

more slowly, more seriously, more quietly, more carefully

- You‟re more patient than me

- The exam was difficult – more difficult than we expected

- Can you walk a little more slowly ?

- I‟d like to have a more reliable car

- I don‟t play tennis much these days I

used to play more often

* You can use –er or more with some two-syllable adjectives, especially:

quiet clever narrow shallow simple

Example: It‟s too noisy here Can we go somewhere quieter / more quiet?

The adjectives and adverbs have irregular comparative forms:

Good/well => better bad/badly => worse far => farther/further

Comparison with as as

You can use as as (but not so as ) in positive sentences and questions:

Example: I‟m sorry I‟m late I got here as fast as I could

There‟s plenty of food You can have as much as you want

Can you send me the money as soon as possible, please ?

Tom isn‟t as old as he look (= Tom is older than he is.)

It‟s not warm, but it isn‟t so cold as yesterday

Less (than) is similar to not as (as):

I spent less money than you ( = I didn‟t spend as much money as you.)

The shopping mall was less crowded than usual (= It wasn‟t as crowded as usual.)

You can also use twice as as , three time as as , etc

Gas is twice expensive as it was a few years ago

Their house is about three times as big as ours

We say the same as (not the same like):

Ann‟s salary is the same as mine Or Ann makes the same salary as me

Tom is the same age as Brian

D Superlatives

The superlative form is –est or most In general, we use –est for short words and

most for longer words (The rules are the same as those for the comparative.)

long – longest hot – hottest easy – easiest hard – hardest

but most famous most boring most difficult most expensive

These adjectives are irregular:

good – best bad – worst far – farthest/furthest

We normally use the before a superlative (the longest / the most famous, etc.)

Yesterday was the hottest day of the year

That was the most boring movie I‟ve ever seen

Why does he always come to see me at the worst possible moment ?

After superlative we use in with places (town, buildings, etc.)

What is the longest river in the world? (not of the world)

We had a great room It was one of the nicest in the hotel (not of the hotel)

PRACTICE

I Complete the sentences with adverbs The first letters of each adverb are given

1 We didn‟t go out because it was raining h _

2 Our team lost the game because we played very ba _

3 I had no trouble finding a place to live I found an apartment quite ea

4 We had to wait for a long time, but we didn‟t complain We waited pat _

5 Nobody knew Steve was coming to see us He arrived unex

6 Mike stays in shape by playing tennis reg

II Put in the right word

1 The driver of the car was _ injured (serious/seriously)

2 I think you behaved very _ (selfish/selfishly)

3 Kelly is _ upset about losing her job (terrible/terribly)

4 There was a _ change in the weather (sudden/suddenly)

5 Everybody at the party was _ dressed (colorful/colorfully)

6 Linda likes wearing _ clothes (colorful/colorfully)

7 She fell and hurt herself quite _ (bad/badly)

8.These pants started coming apart after I wore them only once They‟re _ made (bad/badly)

9 Don‟t go up that ladder It doesn‟t look _ (safe/safely)

10 He looked at me _ when I interrupted him (angry/angrily)

III Rewrite these sentences so that they have the same meaning

1 Jack is younger than he looks

Jack isn‟t

2 I didn‟t spend as much money as you

You

3 The station was nearer than I thought

The station wasn‟t

4 I go out less than I used to

IV Write sentences using the same as

1 Sally and Kate are both 22 years old Sally is

2 You and I both have dark brown hair Your hair

3 I arrived at 10.25 and so did you I

4 My birthday is April 5 Tom‟s birthday is April 5, too My

V Complete the sentences Use a superlative (-est or most ) + a preposition

1 It‟s a very nice room It‟s the hotel

2 It‟s a very cheap restaurant It‟s the town

3 It‟s a very happy day It was my life

4 She‟s a very intelligent student She the class

5 It‟s a very valuable painting It the gallery

6 Spring is a very busy time for me It the year

7 He‟s a very rich man He‟s one of the world

8 It was a very bad experience It my life

9 It‟s a very good college It‟s one the state

10 He‟s a very dangerous criminal He the country

VI Complete the sentences Use a superlative (-est or most ) or a comparative (-er or more )

1 We stayed at the cheapest hotel in town (cheap)

2 Our hotel was cheaper than all the other hotels in the town (cheap)

3 The United State is very large, but Canada is (large)

4 What‟s _ river in the world ? (long)

5 He was a little depressed yesterday, but he looks _ today (happy)

6 It was an awful day It was days of my life (bad)

7 What is _ sport in your country ? (popular)

8 Everest is _ mountain in the world It is _ than any other mountain (high)

9 We had a great vacation It was one of the _ vacation we‟ve ever had (enjoyable)

10 I prefer this chair to the other one It‟s _ (comfortable)

11 What‟s way of getting from here to the bus station? (quick)

12 Mr and Mrs Brown have three daughters is 14 years old (old)

- o0o -

UNIT 4: FORCES IN ENGINEERING

A Reading: Predicting

As you learn in unit 1, it is important to think about what you are going to read before you read Do not start to read a text immediately One way to help you reading is to think about the words which might appear in the text The title might help to focus your thoughts

Which words might appear in a text with the title Forces in Engineering ?

1 The text you are going to read is called Forces in Engineering Here are some

of the words it contains Can you explain the links between each word and the title of the text?

Now read the text Use the information in the text to check the explanation you made above

Forces in engineering

To solve the ship problem, we must look at the forces on the ship (Fig.1) The weight,

W, acts downwards That is the gravity force The buoyancy force, B, acts upwards Since the ship is in equilibrium, the resultant force is zero, so the magnitude of B and W must be the same

Another very important force in engineering is the one caused by elasticity A good example of this is a spring Springs exert more force the more they are stretched This property provides a way of measuring force A spring balance can be calibrated in newtons, the unit of force The block in Fig.2 has a weight of 10 newtons The weight on the balance pulls the spring down To give equilibrium, the spring pulls up to oppose that weight This upward force, F1, equals the weight of the block, W

It is important to get the distinction between mass and weight absolutely clear Mass is the quantity of matter in an object Weight is the force on that object due to gravity Mass is measured in kilograms, whereas weight, being a force, is measured in newtons

We have looked at the buoyancy, elasticity, and gravity There is a fourth force important in engineering, and that is friction Friction

is a help in some circumstances but a hindrance in others Let us examine the forces on the box (Fig.3) Firstly, there is its weight,

W, the gravity force, then there is the reaction, R, normal to the plane R and W have a resultant force trying to pull the box down the slope It is the friction force, F, acting up the slope, that stop it sliding down

B Language study: 1 Grammar links in texts

One of the ways in which sentences in a text are held together is by grammar links In

this extract, note how each expression in italics links with an earlier expression

Another very important force in engineering is the one caused by elasticity A good example of this is a spring Springs exerts more force the more they are stretched This

property provides a way of measuring force

Sometimes these links cause problems for readers because they cannot make the right connection between words in different parts of a text

Study these common grammar links:

1 A repeated noun becomes a pronoun

Springs becomes they

2 A word replaces an earlier expression

Forces in engineering becomes one

3 A word replaces a whole sentence or clauses

Springs exerts more force the more they are stretched becomes this property With which earlier expressions do the words in italics link ? Join them as in the example above

Friction in machine is destructive and wasteful It causes the moving parts to wear and it produces heat where it is not wanted Engineers reduce friction by using very highly polished materials and by lubricating their surfaces with oil and grease They also use ball bearings and roller bearings because rolling objects cause less friction than sliding ones

(Source: S Larkin and L Bernbaun (eds.), The Penguin Book of the Physical World)

2 The present passive: Study these instructions for a simple experiment on friction

1 Place a block of wood on a flat surface

2 Attach a spring balance to one end of the block

3 Apply a gradually increasing force to the balance

4 Note the force at which the block just begins to move

5 Pull the block along so that it moves at a steady speed

6 Note the force required to maintain movement

7 Compare the two forces

When we describe this experiment, we write:

A block of wood is placed on a flat surface A spring balance is attached to one end of

the block

This description uses the present passive We form the present passive using

is/are + past participle

Complete this description of the experiment using the present passive

A block of wood …1… on a flat surface A spring balance …2… to one end of the block A gradually increasing force …3… to the balance The force at which the block just begins to move …4… The block …5… along at a steady speed The force required to maintain movement …6… The two forces …7… It is found that the first force is greater than the second

(This experiment show that the force required to overcome static friction is greater than the force required to overcome sliding friction)

C Word study: Verbs and related nouns

Each of the verb in column A has a related noun ending in –er or –or in column B

Complete the blanks Use a dictionary to check any spellings which you are not certain about For example: refrigerate (a verb) - refrigerator (a noun)

sự cân bằng lực trọng trường lực tương đương, tổng lực được chuẩn hóa, được xác định

sự khác biệt dốc

- o0o -

LANGUAGE IN FOCUS

Making Questions

In questions, we usually put the first auxiliary verb (AV) before the subject (S)

S + AV AV + S Tom will => Will Tom? Will Tom be here tomorrow?

You have => Have you? Have you been working hard?

I can => Can I? What can I do for you?

The house was => was the house? When was the house built?

In simple present questions, we use do/does:

Do you live near here?

What time does the movie begin?

In simple past questions, we use did:

Did you sell your car?

How did the accident happen?

But do not use do/does/did if who/what / which is the subject of the sentence

Emma phoned somebody => Who did Emma phone?

Somebody phoned Emma => Who phoned Emma?

More examples: - Who wants something to eat? (not who does want)

- What happened to you last night? (not what did happen)

- Which bus goes downtown? (not which bus does go)

Note the position of prepositions in questions beginning Who/What/Which/Where ?

- Who do you want to speak to?

- Which job has Jane applied for?

- What was the weather like yesterday?

- Where are you from?

Subject –Verb Agreement

A verb must match its subject in number, singular subjects take singular verbs, and plural subjects take plural verbs

Basic Subject-Verb Agreement

My friend is/was/has/does

My friends are/were/have/do

Frequently Asked Question Typed

A When the subject and verb are split:

The teacher, along with his students, wants to play soccer

The institute that helps them is financially supported by the government

The instructor, as well as his students, has welcomed the school‟s decision

of the uniform

Note: The number of a subject is not affected by a phrase or clause that separates the

subject from its verb

B When the subject is an expression of time, distance, price, and weight

Ten dollars is too much for a drink

Twenty miles is too long a way to walk in a day

Twenty minutes is not enough time for me to get there

C When a fraction or its equivalent initiates a subject:

Two-thirds of the land has been sold

Two-thirds of them are students

Note: In these cases, the noun in the of-phrase determines the number of the verb

D When a subject begins with either A or B, neither A nor B, or not only A but (also) B

Either he or his pupils are going to help us

Not only John but his parents want to help us

Note: When these expressions initiate a subject, the verb must agree with B in number

E When a subject consists of a proper noun or a branch of learning ending in -s:

The United State has a population of over 265 million people

Mathematics is my favorite subject

Physics has been studied for many centuries

F When a subject contains expressions like every, each, more than one, many a, etc

More than one person has applied for that position

Every girl and boy was upset because of the outcome

G When a subject contains expressions like many of, a number of, a couple of, a group of, a few, several, both, etc

A number of my friends are from China

Many countries have joined the European Union

Several cars were damaged in the accident

-

PRACTICE

I Ask Joe questions (look at his answers before you write the questions)

1.(where / from?) - From Toronto originally

2 (where /live / now?) - In Vancouver

3 (married?) - Yes

5 (children?) - Yes, three boys

6 (how old / they?) - They‟re 4, 7, and 9

7 (what / wife / do?) - She‟s a police officer

8 (she / like her job?) - Yes, very much

II Make questions with who or what

1 Somebody gave me the key -

2 Something happened -

3 Diane told me something -

4 The book belongs to somebody -

5 Somebody lives in that house -

6 I fell over something -

7 Something fell on the floor -

8 This word means something -

9 I borrowed the money from somebody -

10 I‟m worried about something -

III Choose the best word or phrase that best completes the sentence

1 cats as faithful as dogs?

2 Mathematics the study of numbers, quantities, or shapes

3 Each book _ unique illustrations

4 The people _ lining up to get on the train

5 The captain, together with his crew members, _ struggling to control the ship

6 Each of our products _ guaranteed for sixty years

7 A number of researchers _ expected to attend the conference

8 Two thirds of the land already been sold

9 Not only the teacher but the students opposed to the new uniforms

10 Three hours _ too short a time for us to talk about this matter

11 Could you me a big favor?

12 He must have missed the train; otherwise, he arrived by now

13 There were plenty of people who _ black

A was wear B was wearing C wearing D were wearing

14 He is earning ten dollars an hour, which not a small amount of money

15 His daughter is married a doctor

-UNIT 5: THE ELECTRIC MOTOR

A Reading: Skimming

In Unit 2 you studied scanning – locating specific information quickly Another useful strategy is reading a text quickly to get a general idea of the kind of information it contains You can then decide which parts of the text are worth reading in more detail later, depending

on your reading purpose This strategy is called skimming

1 Skim this text and identify the paragraphs which contain information on each

of these topics The first one has been done for you

a What electric motors are used for Paragraph 1

A electric current running through a wire produces a magnetic field around the wire If

an electric current flows around a loop of wire with a bar of iron through it, the iron becomes magnetized It is called an electromagnet; one end becomes a north pole and the other a south pole, depending on which way the current is flowing around the loop (see Figure 1)

If you put two magnets close together, like poles – for example, two north poles – repel each other, and unlike poles attract each other

In a simple electric motor, like the one showed in Fig 2, a piece of iron with loops of wire round it, called an armature, is placed between the north and south poles of a stationary magnet, known as the field magnet When electricity flows around the armature wire, the iron becomes an electromagnet (see Figure 2)

The attraction and repulsion between the pole of this armature magnet and the poles of the field magnet make the armature turn As a result, its north pole is close to the south pole of the field magnet Then the current is reversed so the north pole of the armature magnet becomes the south pole Once again the attraction and repulsion between it and the field magnet make it turn The armature continues turning as long as the direction of the current, and therefore its magnetic poles keeps being reversed

To reverse the direction of the current, the ends of the armature wire are connected to different halves of a split ring called a commutator Currents flow to and from the commutator through small carbon blocks called brushes As the armature turns, first one half of the commutator comes into contact with the brush delivering the current, and then the other, so the direction of the current keeps being reversed

(Source: adapted from „Inside out: Electric Motor‟, Education Guadian)

2 Match each of these diagrams with the correct description a, b, c or d One of

the description does not match any of the diagrams.(The diagrams are in the correct sequence, but the descriptions are not.)

a The armature turn a quarter of a turn Then electric contact is broken because of the

gap in the commutator, but the armature keeps turning because there is nothing to stop it

b When the current flows, the armature becomes an electromagnet Its north pole is

attracted by the south pole and repelled by the north pole of the field magnet

c When an universal motor is run on direct current, the magnetic poles in the armature

change while those of the field magnet remain constant

d When the commutator comes back into contact with the brushes, current flows

through the armature in the opposite direction Its poles are reversed and the turn continues

B Language study: 1 Describing function

Try to answer this question: „What does an electric motor do ?‟

When we answer a question like this, we describe the function of something We can describe the function of an electric motor in this way:

An electric motor converts electrical energy to mechanical energy

We can emphasize the function like this:

The function of an electric motor is to convert electrical energy to mechanical energy Match each of these motor components to its function, and then describe its function in

a transfer rotation from the motor

b create an electromagnet field

c converts electromagnetic energy to rotation

d reverses the current to the armature

e support the drive shaft

f supply current to the armature

2 Describing components

Now study this description of the motor

A simple dc motor consists of a field magnet and an armature The armature is placed between the poles of the magnet The armature is made up of a loop of wire and a split ring known as a commutator The loop is connected to the commutator Current is supplied to the motor through carbon blocks called brushes

To write a description, you need to use language to:

1 dismantle a piece of equipment into its main parts These expression will help:

A A consists of X and Y

Is made up of

Is composed of

The loop is connected to the commutator

Use the following words to complete the text:

Are made up / is placed / is composed / consists

A transformer ……… Of two coils, a primary and a secondary The coils are wound on a former which is mounted on a core The coils ……… of a number of loops of wire The core ……… of thin pieces of soft iron U- and T- shaped pieces are used The former

…… on the leg of the T

C Word study: Verbs with –ize /-ise

Study these statement: The rotor is magnetized

What does it mean? Can you say it another way? We can rewrite this statement as:

The rotor is made magnetic

Verbs ending in –ize / -ise have a range of meanings with the general sense of

„make + adjective‟

Rewrite these sentences replacing the phrases in italics with appropriate –ize/-ise

1 Some cars are fitted with a security device which makes the engine immobile

2 In areas where the power supply fluctuates, for sensitive equipment a device to

make the voltage stable is required

3 Manufacturers seek to keep costs to a minimum and profits to a maximum

4 Most companies have installed computers to control their production line

5 Companies may make their operation more rational by reducing the variety of

products they make

New words and expressions:

- the direction of the current:

- carbon blocks / brushes:

cổ ghóp lõi sắt, phần ứng nam châm điện

từ trường dòng điện một chiều dòng điện xoay chiều cuộn dây điện

đẩy hút chiều dòng điện chổi than

Further reading:

Portable generator

Although most electricity comes from power stations, power can also be generated by far smaller means Nowadays, electricity generators can be small enough to hold in the hand Portable generators are made up of two main parts: an engine, which powers the equipment, and an alternator, which convert motion into electricity

The engine runs on petrol It is started by pulling a cord This creates a spark inside which ignites the fuel mixture

In a typical four-stroke engine, when the piston descends, the air inlet valve opens and a mixture of air and petrol is sucked in through a carburetor

The valve closes, the piston rises on the compression stroke and a spark within the upper chamber ignites the mixture This mini-explosion pushes the piston back down, and as

it rises again the fumes formed by the ignition are forced out through the exhaust valve This cycle is repeated many times per second The moving piston makes the crankshaft rotate at great speed

The crankshaft extends directly to an alternator, which consists of two main sets of windings – coils of insulated copper wire wound closely around an iron core One set, called stator windings, is in a fixed position and shaped like a broad ring The other set, the armature windings, is wound on the rotor which is fixed to the rotating crankshaft The rotor makes about 3,000 revolutions per minute

The rotor is magnetized and as it spins round, electricity is generated in the stator windings through the process of electromagnetic induction The electric current is fed to the output terminals or sockets

This type of generator can produce a 700 watt output, enough to operate lights, television, and some domestic appliances Larger versions provide emergency power to hospitals and factories

The four-stroke cycle

In the four-stroke cycle, the piston descends on the intake stroke, during which the inlet valve is open The piston ascends on the compression stroke with both valves closed and ignition takes place at the top of the stroke The power or expansion stroke follows The gas generated by the burning fuel expands rapidly, driving the piston down, both valves remaining closed The cycle is completed by the exhaust stroke, as the piston ascends once more, forcing the products of combustion out through the exhaust valve The cycle then repeats itself

(Source: Adapted from „Inside out: Portable generator‟, Education Guardian)

Questions:

1 What are its main parts?

2 What does the engine run on?

3 What are the four strokes called?

4 What is the function of the crankshaft?

5 What do both stator and rotor have?

6 What is the difference between stator and rotor?

LANGUAGE IN FOCUS

Gerunds and Infinitives

Infinitives: An infinitive is the base form of a verb with to preceding it

A Use a to-infinitive after the following common verbs: agree, decide, expect, happen,

pretend, promise, manage, tend

He decided to go home

B Use a to-infinitive after the following common verbs plus their object: advise, allow, expect, forbid, want, force, tell

His manager allowed him to go home

C Use an infinitive without to after the common following verbs plus their object: have, let, make, feel, see, hear, smell, find

He let Tom go home

Gerunds: A gerund is the –ing form of a verb It is used as a noun

Use an –ing form after the following common verbs: avoid, can‟t help, deny, feel like, give up, imagine, mind, postpone, enjoy

He denies eating the cake

Choosing Between Infinitives and Gerunds

A gerund is always used when a verb is followed by a preposition: admit to, approve of, argue about, believe in, care about, complain about, concentrate on, confess to

They apologized for being late

He dreamt about eating a hamburger

The following common verbs allow both a to-infinitive form and an –ing form Sentences with either form will have the same meaning They are: attempt, begin, continue, hate, like, love, neglect, prefer, regret, stand/can‟t stand, start

He hates running

He hates to run

The following common verbs allow both a to-infinitive form and an –ing form However, their meanings are different in each case: remember, forget, stop, regret, try

I forgot to turn the light off (= I didn‟t turn it off, and it remained on)

I forgot turning the light off (= I actually turned it off I forgot that I had done that.)

Note: The choice of a to-infinitive or an –ing form depends on the meaning

Choosing Subjects

A Use objective case pronouns with an infinitive

expect him to help her

allow them to do it

let him go

B Use a possessive pronoun with a gerund

enjoy their singing

mind my smoking

Some more verbs followed by –ing Some more verbs followed by to-infinitive

finish avoid consider admit miss

involve quit postpone delay imagine

deny risk practice

offer decide hope deserve attempt mean promise agree plan aim afford manage intend threaten refuse arrange learn need fail

-

PRACTICE

I Put the verb into the correct form, to-infinitive or –ing form

1 When I‟m tired, I enjoyed _ TV It‟s relaxing (watch)

2 It was a nice day, so we decided for a walk (go)

3 There was a lot of traffic, but we managed _ to the airport in time (get)

4 I‟m not in a hurry, I don‟t mind (waiting)

5 They don‟t have much money They can‟t afford _ out very often (go)

6 We‟ve got a new computer in our office I haven‟t learned how _ it yet (use)

7 I wish that dog would stop _ It‟s driving me crazy (bark)

8 Our neighbor threatened _ the police if we didn‟t stop the noise (call)

9 We were all afraid to speak Nobody dared anything (say)

10 We were hungry, so I suggested _ dinner early (have)

II Choose the word or phrase that best completes the sentences

1 Who does she to take care of her ?

2 I can‟t afford _ a new car

3 They are considering to Atlanta

4 I would like _ by your office on my way home

5 I seldom forget my teeth before going to bed

A brush B to brush C brushing D brushed

6 They politely asked me _ in another place

7 Since we live by an airport, we can easily watch the airplanes off

A take B to take C be taking D will take

8 We think him to have access to the Internet is a bad idea

A allow B to allow C allowing D allowance

9 My son is not very good at _ yet

A drive B to drive C driving D will drive

10 They were heard _ goodbye to their friends

11 Now we are going to _ about our plans for next year

12 Please keep me as to his whereabouts

A interred B informed C deformed D reformed

13 I‟m looking forward to from you soon

14 Mother _ me clean the floor with a mop

15 Nobody is opposed your suggestion

o0o

PART II: THE AGRICULTURAL MACHINERY

………

General

1 The importance of agricultural tractors in the world today should never be

under-estimated They provide a great source of power which has almost entirely replaced the power

of horse, and of man, for the many heavy and time-consuming tasks carried out on land

2 This power is being used to produce food for the nations of the world and there is no

more important task than this A tractor can do the work of numerous horses, and do this work

in the same time, without having to be rested to recover from fatigue Provided reasonable attention is given to its lubrication and it is kept supplied with fuels, it will work on indefinitely The driver, of course, will require his rest, but it is not unusual for tractors to work around the clock when relief drivers are available

3 As more and more food production is required to feed the ever-increasing world

population, the numbers of tractors used will increase to meet the demand Great areas of land will yet be brought into food production and the tractor will supply the necessary power for the work

Tractor Types

4 The present-day tractor is a most useful machine, capable of supplying its power to

numerous farm tasks The most power absorbing of these tasks is usually the basic cultivation

of land; therefore the tractor is designed to be able to do this task whilst at the same time being amply powered for the many other field tasks it is required to do, such as drilling seed, top dressing, spraying, haulage, etc

5 During the years since the First World War, and in particular during, say, the last 20

years, a great amount of progress has been made in developing a machine capable of operating efficiently a very wide range of implements and machines Many devices have been incorporated in the mechanism of the tractor for this purpose

6 The type of tractor used on the land depends on the type of work to be done

Track-Laying Tractors (Fig 1)

7 These tractors are sometimes referred to as “crawlers” and are usually tractors with a

large horse-power and capable of doing very heavy work On farms, they may be used for pulling a five- or six- furrow plough or for heavy cultivation Yet, On the other hand, there is

a very small track-laying tractor of no more than 6 h.p (horse-power) which is used for work

on market gardens

Heavy Wheeled Tractors

8 Not only track-laying tractors are used for the heavy work on farms Very large

four-wheel-drive tractors are now common which are capable of pulling up to twelve furrow ploughs with engines of up to 500 h.p These large tractors may be equipped with twin wheels all round, and no longer run in the furrow when ploughing, but run on top in the same way as

a crawler tractor They also carry out very heavy cultivation

Fig.1 A track-laying tractor

General-purpose Tractors (Fig.2)

9 The general-purpose tractor is a wheeled tractor and the lighter type may be powered

by an engine of about 40 h.p whilst the other type may have an engine of 100 h.p Either one

or both of these types may be used on most farms and they are the most common type used today

Fig 2 A General-purpose tractor

Two-wheeled Tractors

10 Another type of tractor to be found on many small holdings and market gardens is

the hand-operated This type is powerful enough to do light cultivation and is steered by a walking operator

11 Most tractors nowadays are powered by internal combustion engines, which,

although they may vary slightly between one make and another as regards detail of construction, operate on the same basic principles