BÀI TẬP TIẾNG ANH LỚP 11 UNIT 11 SOURCES OF ENERGY A. MULTIPLE CHOICES: I/ Select the synonym of the following bold and underlined word in each sentence in the unit: 1/ At present, most of our energy comes from fossil fuels (oil, coal, and natural gas). A. Recently B. Now C. That day D. In fact 2/ However, such reserves are strictly limited. A. exactingly B. particularly C. severely D. faithfully 3/ Because power demand is increasing very rapidly, fossil fuels will be exhausted within a relatively short time. A. emptied B. emptied C. tired D. bushed 4/ Therefore, people must develop and use alternative sources of energy. A. hold up B. build up C. grow up D. stand up 5/ Nuclear energy can provide enough electricity for the world’s needs for hundreds of years, but it can be very dangerous. A. uninteresting B. troublesome C. enormous D. hazardous 6/ The heat coming from deep inside the earth is called geothermal heat. A. profound B. sincere C. severe D. artful 7/ However, it is only possible in few places in the world. A. able B. skilful C. available D. potential 8/ It is a clean source of energy. A. tidy B. innocent C. thorough D. straight 9/ This energy is useful because it can create electricity. A. produce B. do C. design D. shape 10/ The sun releases large amounts of energy every day. A. lets out B. lets by C. lets down D. lets into II/ Select the antonym of the following bold and underlined word in each sentence in the unit: 1/ At present, most of our energy comes from fossil fuels (oil, coal, and natural gas). A. incidental B. individual C. irregular D. impossible 2/ However, such reserves are strictly limited. A. loosely B. tolerantly C. permissively D. carelessly 3/ Because power demand is increasing very rapidly, fossil fuels will be exhausted within a relatively short time. A. falling B. pausing C. reducing D. stopping 4/ Nuclear energy can provide enough electricity for the world’s needs for hundreds of years, but it can be very dangerous. A. hopeless B. helpless C. useless D. harmless 5/ The heat coming from deep inside the earth is called geothermal heat. A. casual B. shallow C. mild D. direct 6/ Solar energy is not only plentiful and infinite but also clean and safe. A. small B. tiny C. few D. scarce 7/ This energy is useful because it can create electricity. A. worthless B. helpless C. hopeless D. shapeless 8/ However, how to make full use of these sources of energy is a question for researchers all over the world. A. partial B. hungry C. empty D. imperfect 9/ This energy is useful because it can create electricity. A. worthless B. helpless C. hopeless D. shapeless 1 BÀI TẬP TIẾNG ANH LỚP 11 10/ However, how to make full use of these sources of energy is a question for researchers all over the world. A. partial B. hungry C. empty D. imperfect III/ Choose the best answer A, B, C or D for each sentence: 1/ She's a very _______ dresser - she always looks like she's wearing her mother's clothes! A. conserve B. conservative C. conservation D. conservatism 2/ It’s said that dolphins are a _______ species (= it is illegal to harm or kill them). A. protected B. protection C. protective D. protectively 3/ That man has a limited _______ of Chinese. A. know B. knowable C. knowledge D. knowing 4/ Her sister was studying _______ at her desk. A. industry B. industrial C. industrious D. industriously 5/ We know that such data will prove _______ for researchers. A. value B. valued C. valuable D. invaluable 6/ Do you know that representatives of the company claim their plan will be _______ to local needs? A. sense B. sensitive C. sensible D. senseless 7/ He told me that the program traced the _______ of popular music through the ages. A. develop B. developed C. developing D. development 8/ It’s reported that inflation figures have fluctuated _______ between 5% and 25%. A. wildfire B. wildlife C. wild D. wildly 9/ Actually, for a goalkeeper, it's a great _______ to have big hands. A. advantage B. disadvantage C. advantageous D. advantageously 10/ Loan first rose to _______ as a singer at the age of 15. A. fame B. famed C. famous D. infamous IV/ Choose the correct prepositions to complete the sentences: 1/ Yesterday evening they walked slowly _______ the woods. A. on B. through C. along D. across 2/ It’s rumored that they're building a new bridge _______ the river. A. above B. over C. across D. under 3/ We've been in this job for ten years, and we've picked up a good deal of expertise _______ the way. A. along B. in C. on D. by 4/ Remember to make sure the computers are all _______ before you go home. A. in B. on C. out D. off 5/ Long fell _______ several stairs and broke his wrist. A. down B. under C. below D. above 6/ He put his hands _______ his eyes because he couldn't bear to watch. A. above B. over C. on D. between 7/ Both he and his wife are _______ work. A. out of B. for C. on D. in 8/ Stop running around and get _______ bed, Phong! A. on B. in C. onto D. into 9/ Don’t forget to put the books _______ on the top shelf! A. over B. up C. down D. above 10/ She’s been having problems loading this software _______ her computer. 2 BÀI TẬP TIẾNG ANH LỚP 11 A. from B. to C. onto D. into V/ Choose the word whose underlined part has a different pronunciation from the others in each group: 1/ A. na tional B. pla n C. establish D. tha t 2/ A. parks B. trees C. caves D. contains 3/ A. found B. south C. mou ntain D. wou nd 4/ A. located B. formed C. threatened D. agreed 5/ A. West B. Kenya C. re cognize D. taken 6/ A. study B. dry C. variety D. rainy 7/ A. hi ke B. duri ng C. surpri se D. bi ke 8/ A. co ntain B. ano ther C. abando n D. vo cabulary 9/ A. sea son B. fea ture C. increa se D. mea nt 10/ A. loo k B. goo d C. choose D. book VI/ Choose the word whose underlined part has a different pronunciation from the others in each group: 1/ A. na tional B. pla n C. establish D. tha t 2/ A. parks B. trees C. caves D. contains 3/ A. found B. south C. mou ntain D. wou nd 4/ A. located B. formed C. threatened D. agreed 5/ A. West B. Kenya C. re cognize D. taken 6/ A. study B. dry C. variety D. rainy 7/ A. hi ke B. duri ng C. surpri se D. bi ke 8/ A. co ntain B. ano ther C. abando n D. vo cabulary 9/ A. sea son B. fea ture C. increa se D. mea nt 10/ A. loo k B. goo d C. choose D. book VII/ Choose the word whose main stress is placed differently from the others in each group: 1/ A. national B. abandon C. orphanage D. chemical 2/ A. locate B. smallest C. surprise D. depend 3/ A. establish B. visitor C. especial D. expensive 4/ A. contain B. increase C. explain D. faster 5/ A. rainforest B. wilderness C. tropical D. survival 6/ A. butterfly B. endanger C. expression D. acceptance 7/ A. mountain B. ethnic C. fauna D. attack 8/ A. during B. flora C. defeat D. province 9/ A. season B. nearly C. mainly D. delight 10/ A. recognize B. enemy C. yesterday D. responding VIII/ Match the words in column A with their synonyms in column B: A B 1/ locate 2/ contain A/ region B/ warn 3/ surprise 4/ abandon C/ astonish D/ leave 5/ take care of 6/ zone E/ pollute F/ let go 7/ contaminate 8/ threaten G/ plan H/ settle 9/ intend 10/ release I/ carry J/ look after IX/ Match the words in column A with their antonyms in column B: A B 1/ dry 2/ hard A/ independent B/ cold 3/ different 4/ dependent C/ protect D/ soft 5/ tropical 6/ increase E/ alike F/ cheap 7/ start 8/ endanger G/ finish H/ less 9/ more 10/ expensive I/ wet J/ decrease 3 BÀI TẬP TIẾNG ANH LỚP 11 X/ Match the sentences, clauses or phrases in column A with the ones in column B to make meaningful sentences: A B 1/ Can you take care of the children A/ Wait until he has gone. 2/ Before you leave, B/ until I come back. 3/ Wait here C/ If we don’t hurry, we’ll be late. 4/ After I’ve read this book, D/ We’ll get wet if we go out. 5/Don’t say anything while Tom is here. E/ as soon as I finish. 6/ I’ll come F/ you must visit the museum. 7/ You’ll feel better G/ when you have something to eat. 8/ It’s raining. H/ while I am out? 9/ Hurry up! I/ you can have it. 10/ If it rains this evening, J/ I won’t go out. XI/ Find the one mistake (A, B, C or D) in these sentences and then correct them: 1/ He’s been (A) in this job (B) for ten years, and he’s picked (C) down a good deal of expertise (D) along the way. 2/ Getting (A) a coach (B) across country (C) from Ca Mau (D) until Mong Cai can be difficult. 3/ (A) How long that journey took would depend (B) in how (C) long it took to get (D) through the traffic. 4/ We’ve been having (A) matters (B) loading this (C) software (D) onto our computer. 5/ Oanh can't get (A) into those trousers (B) no more. They're (C) far too small (D) for her. 6/ My friend took the job (A) into necessity (B) because he had (C) no money (D) left. 7/ We couldn't hear (A) what he was saying (B) over the noise (C) off the planes taking (D) off. 8/ Does she usually (A) wear her skirts (B) above (C) or (D) under the knee? 9/ To push the number (A) of unit sales (B) up (C) every quarter can't be continued (D) indefinite. 10/ This luggage is (A) really heavy - can we put it (B) down (C) (in the floor) (D) for a while? XII/ Find the one mistake (A, B, C or D) in these sentences and then correct them: 1/ (A) It was (B) a crisis (C) for which she was (D) total unprepared. 2/ He (A) took out (B) a photo (C) of his son, (D) whose he adores. 3/ Cohen, (A) whose contract (B) is expired next week, is likely (C) to move to play for (D) a European club. 4/ (A) For the first few months the babies (B) looked (C) so likely I couldn't tell (D) which was which. 5/ You see (A) where Mira (B) is standing? (C) Well, he's (D) behind her. 6/ I was (A) just getting (B) into the bath (C) when the telephone (D) rings. 7/ (A) It’s that! I'm not putting (B) up with (C) any more of (D) her rudeness. 8/ (A) There was a picture (B) in the paper of a man (C) whose leg (D) had blown off. 9/ Fraud detectives (A) are investigating (B) the company, (C) three of them senior executives have (D) already been arrested. 10/ I hadn't got (A) a lot of money (B) on me (C) but I gave them (D) what I had. 4 BÀI TẬP TIẾNG ANH LỚP 11 XIII/ Read the following passage carefully, and then select the best option A, B, C or D to complete it: WIND POWER Airflows can be used to run wind turbines and some are capable of (1) _______ 5 MW of power. Turbines with rated output of 1.5-3 MW have become the most common for commercial use. The power output of a turbine is a function of the cube of the wind speed, (2) _______ wind speed increases, power output increases dramatically. Areas where winds are stronger and more constant, such as offshore and high altitude sites, are preferred locations for wind (3) _______. Wind power is the fastest growing of the renewable energy technologies. Over the past decade, global installed maximum (4) _______ increased from 2,500 MW in 1992 to just over 40,000 MW at the end of 2003, at an annual growth (5) _______ of near 30%. Due to the intermittency of wind resources, most deployed turbines in the EU produce electricity an average of 25% of their rated maximum (6) _______, (a load factor of 25%), but under favorable wind regimes some reach 35% or higher. The load factor is generally higher in winter. It would (7) _______ that a typical 5 MW turbine in the EU would have an average output of 1.7 MW. Globally, the long-term technical potential of wind energy is believed to be five times current (8) _______ global energy consumption or 40 times current electricity demand. This could require large amounts of land to be utilized for wind turbines, particularly in areas of (9) _______ wind resources. Offshore resources experience mean wind speeds of ~90% greater than that of land, so offshore resources could contribute substantially more energy. This (10) _______ could also increase with higher altitude ground-based or airborne wind turbines. Wind strengths near the Earth's surface vary and thus cannot guarantee continuous power (11) _______ combined with other energy sources or storage systems. Some estimates suggest that 1,000 MW of conventional wind generation capacity can be relied (12) _______ for just 333 MW of continuous power. While this might change as technology evolves, advocates have suggested incorporating wind power (13) _______ other power sources, or the use of energy storage techniques, with this in mind. It is best used in the context of a system that has significant reserve capacity (14) _______ hydro, or reserve load, such as a desalination plant, to mitigate the economic effects of resource variability. Wind power is renewable and produces no greenhouse gases (15) _______ operation, such as carbon dioxide and methane. 1/ A. having B. doing C. producing D. making 2/ A. so that B. in order to C. so as to D. so as 3/ A. farms B. places C. spots D. lands 4/ A. energy B. ability C. capability D. capacity 5/ A. rate B. rank C. height D. level 6/ A. energy B. power C. speed D. light 7/ A. mean B. say C. rumor D. suggest 8/ A. produce B. producer C. product D. production 9/ A. taller B. higher C. faster D. better 10/ A. picture B. image C. number D. figure 11/ A. if B. unless C. even if D. provided that 12/ A. in B. into C. on D. onto 13/ A. to B. by C. for D. with 14/ A. in order for B. such as C. as well as D. for instance 15/ A. during B. before C. after D. by 5 BÀI TẬP TIẾNG ANH LỚP 11 XIV/ Read the following passage carefully, and then select the best option A, B, C or D to complete it: National Parks and Preserves, (1) _______ public lands or bodies of water within a country, set aside by the (2) _______ to protect ecosystems, plant and animal species, scenic landscapes, geologic formations, or historical or archaeological (3) _______. National parks are managed primarily for public recreation, (4) _______ exceptional locations where visitors can view wildlife and enjoy the (5) _______. Generally, these protected public lands are off-limits to hunting, livestock grazing, logging, mining, and other (6) _______ that exploit natural resources. Some parks commemorate significant historical events. (7) _______, Gettysburg National Military Park (1895) in Pennsylvania conserves the 13 sq km (5 sq mi) site of the pivotal battle in the (8) ______ Civil War (1861-1865). National preserves, sometimes (9) _______ nature or wildlife reserves, often are located within or near national (10) _______. These lands are managed by national governments primarily for wildlife protection or scientific research (11) _______ recreation, and provide “living laboratories” in (12) _______ scientists observe plant and animal species in their natural habitat. (13) _______, fishing, and mining are permitted within many United States preserves (14) _______ the activities do not harm natural resources. Many other countries specifically ban such activities in their (15) _______ . New vocabulary: - ecosystem (n.): hệ sinh thái - off-limits (adj.- after verbs): (thuộc vùng đất) cấm vào - livestock (n.): vật nuôi, thú nuôi - to commemorate (v.): kỷ niệm, tưởng nhớ - pivotal (adj.): then chốt, mấu chốt, chủ chốt 1/ A. one B. only C. unique D. just 2/ A. hospital B. school C. country D. government 3/ A. sites B. places C. spots D. lands 4/ A. giving B. providing C. sending D. throwing 5/ A. joy B. fun C. outdoors D. indoors 6/ A. things B. activities C. people D. animals 7/ A. In fact B. Moreover C. However D. For example 8/ A. American B. African C. British D. French 9/ A. told B. considered C. called D. known 10/ A. parks B. places C. sites D. resources 11/ A. such as B. in spite of C. because of D. instead of 12/ A. whom B. that C. which D. what 13/ A. Hiking B. Swimming C. Camping D. Hunting 14/ A. if B. unless C. when D. that 15/ A. places B. preserves C. lands D. countries B. USE OF ENGLISH: I/ Match the sentences, clauses or phrases in column A with the ones in column B to make meaningful sentences: A B 1/ Can you look after my house A/ as soon as we finish our work. 2/ Before you and your classmates leave the room, B/ you can have it. 3/ Please wait for me here C/ You’ll possibly get wet as you go out without an umbrella. 4/ After we’ve read the magazine, D/ we will still stay in. 5/ Remember not to say anything while E/ remember to turn off the lights. 6 BÀI TẬP TIẾNG ANH LỚP 11 Huy is here. 6/ We’ll come to the festival F/ If you don’t hurry, you’ll miss the train. 7/ You’ll feel better G/ when you have something to drink. 8/ I think it’s going to rain. H/ Wait until he has gone far away. 9/ Now, come on! Hurry up! I/ until I come back with our lunch. 10/ If it snows this afternoon, J/ while I go out on my business for a few days? II/ Supply the correct form of the word in brackets: 1/ All that needless (worry) _______ over what we'd say to her at the party, and she wasn't even there! 2/ Thank you very much for a really (wonder) _______ evening. 3/ Her sons rarely show any (appreciate) _______ for what she does for them. 4/ He said that the royal (engage) _______ was announced officially this morning. 5/ Is it true that modern cosmology believes the Universe to have come into (exist) _______ about fifteen billion years ago? 6/ Her main concern is to (sure) _______ her own political survival. 7/ Do you know that the Eiffel Tower in Paris is an instantly (recognize) _______ landmark? 8/ I believe that you can predict changes with a (surprise) _______ degree of accuracy. 9/ The woman’s reputation was destroyed when she was caught (steal) _______ some money. 10/ He just seems so sad and he doesn't know what the (solve) _______ is. III/ Put in the correct verb form: 1/ If I (be) _______ him, I (help) _______ his friends now. 2/ If you (be) _______ late, you will be punished by your teacher. 3/ They could have understood her if she (speak) _______ more slowly. 4/ What (you/do) _______ if you (be) _______ a millionaire? 5/ She didn’t pay attention to the teacher’s explanation. If she (pay) _______ more attention, she (do) _______ the exam well. 6/ He’s waiting for his uncle to come back from Hue. If his uncle (come) _______ home, he (have) _______ a lot of gifts. 7/ Nhung is a naughty girl and often makes fun of her roommates. If she (start) _______ a joke, someone (cry) _______ bitterly. 8/ Linh wanted to buy some presents for her younger brother but she couldn’t. If she (afford) _______ to buy, her younger brother (be) _______ happy to greet a new year. 9/ That girl is never willing to help poor people. If she (do) _______ something, the earth (stop) _______ moving. 10/ We didn’t know that his mother was ill. If we (know) _______ that, we (come) _______ to visit her. I V/ Complete the sentences with the most suitable preposition: 1/ We can walk _______ here _______ the station _______ under fifteen minutes. 2/ The goats were loaded _______ trucks. 3/ They struggled _______ the crowd _______ they reached the front. 4/ Have a look! The helicopter is hovering _______ the building. 5/ Do you know that if we cut _______ the field, it'll save time? 6/ He opened the window and stuck his head _______. 7/ Fortunately, nobody was _______ the building when it collapsed. 8/ Don’t you hear the bells ring _______ regular intervals _______ the day? 9/ The boy took the money _______ his mother's purse, _______ himself. 7 BÀI TẬP TIẾNG ANH LỚP 11 10/ It’s not good to drive _______ more _______ three hours _______ taking a break. V/ Complete the second sentence using the word given in brackets beginning as shown: 1/ The woman was so furious that she couldn’t contain herself. (express) → The woman ______________________________________________. 2/ Do you remember that this can contains ten liters? (hold) → This can _________________________________________________? 3/ You could go into the city but it’s a real hike from here. (way) → You could go into town _____________________________________. 4/ We can’t survive on 10 VND a week. (needs) → 10 VND is not enough ______________________________________. 5/ There are only several survivors from the original team.(replaced) → Only several members remain ________________________________. 6/ The girl will cope. She’s one of life’s great survivors. (situations) → The girl deals very well _____________________________________. 7/ The farmers usually depend on their good harvest for their very existence. (continue) → The farmers usually depend on _______________________________. 8/ He takes high delight in proving others wrong. (enjoys) → He _____________________________________________________. 9/ The little girl is not tall enough to reach the cake on the table. (short) → The little girl _____________________________________________. 10/ Our mother asked us to bring the chairs into the kitchen. (had) → Our mother ______________________________________________. VI/ Put the statements in past unreal conditions: 1/ Trang didn’t know how to solve the problem so she got poor marks. → If Trang _________________________________________________. 2/ You didn’t say sorry so our teacher got angry. → If you ___________________________________________________. 3/ He didn’t pass the exam and his family were very sad. → If he ____________________________________________________. 4/ It rained heavily yesterday morning so we couldn’t go out. → If it _____________________________________________________. 5/ The weather was not fine enough so we didn’t go fishing. → If the weather _____________________________________________. 6/ His computer broke down and he had to stop his work. → If his computer ____________________________________________. 7/ Hanh was angry so her friends didn’t say anything to her. → If Hanh __________________________________________________. 8/ Many friends of hers couldn’t come so she canceled the party. → If many friends ____________________________________________. 9/ Minh was interested in playing games so he didn’t study his lesson. → If Minh __________________________________________________. 10/ Our teacher had a bad headache yesterday so he didn’t go to school. → If our teacher _____________________________________________. VII/ Read the following passage carefully, and then complete it with the words or phrases provided: The transfer of energy ; having no direction in space ; In other words ; with its origins in physics via work ; that is ; no moment of time is different than any other ; For example; The word "energy" ; "Please conserve energy" ; which is a function of coordinate time derivatives only ; 8 BÀI TẬP TIẾNG ANH LỚP 11 Energy is an important concept in science, (1) _______, and it is very convenient quantity which thus finds applications throughout the natural sciences. Energy is subject to a strict global conservation law; (2) _______, it can neither be created nor destroyed. This law mathematically follows from shift symmetry of time ((3) _______) and mathematical definition of energy. The total energy of a system can be subdivided and classified in various ways. (4) _______, it is sometimes convenient to distinguish potential energy (which is a function of coordinates only) from kinetic energy ((5) _______). It may also be convenient to distinguish gravitational energy, electrical energy, thermal energy, and other forms. These classifications overlap; for instance thermal energy usually consists partly of kinetic and partly of potential energy. (6) _______ can take various forms; familiar examples include work, heat flow, and advection, as discussed below. (7) _______ is also used outside of physics in many ways, which can lead to ambiguity and inconsistency. The vernacular terminology is not consistent with technical terminology. For example, the important public- service announcement, (8) _______ uses vernacular notions of "conservation" and "energy" which make sense in their own context but are utterly incompatible with the technical notions of "conservation" and "energy" (such as are used in the law of conservation of energy). In classical physics energy is considered a scalar quantity, (9) _______. In special relativity energy is also a scalar (although not a Lorentz scalar but a time component of the energy-momentum 4-vector). (10) _______, energy is invariant with respect to rotations of space, but not invariant with respect to rotations of space-time (= boosts). VIII/ Read the passages and titles below carefully, and then put the titles where they should be: “What’s A National Park?; Yellowstone National Park; What Makes Yellowstone So Special?; Where Is Yellowstone?; Welcome Back Wolves; Other Natural Wonders; Old Faithful” A. __________ Picture a place where you can see smelly gray mud bubbling up from the ground and steaming hot water shooting out of rocks. In the distance, high waterfalls tumble through colorful canyons. It may sound like make-believe, but you can find all these things in Yellowstone National Park. Yellowstone is in the United States and it’s the oldest national park in the world. B. __________ A national park is land set aside by the government in order to protect it. Yellowstone was made a national park in 1872. People realized it was a very special place that should be preserved. National parks are also created so people can enjoy nature. In Yellowstone, you can do things such as camp, hike in the woods, ride horses, and go fishing. C. __________ Yellowstone sits in the Rocky Mountains. Most of Yellowstone is in the northwest corner of Wyoming. But parts are in Idaho and Montana, too. D. __________ The ground beneath Yellowstone contains a large amount of hot melted rock, called magma. The magma heats water in the ground. The steaming water pushes to get to the surface, much like steam whistling from a boiling teapot. 9 BÀI TẬP TIẾNG ANH LỚP 11 Sometimes the heated water forms a geyser. A geyser is a place where hot water spouts up from underground. There are more than 300 geysers in Yellowstone, some big and some small. Other times the hot water seeps from the ground as a hot spring. There are even more hot springs in Yellowstone than geysers. If you explore Yellowstone, you may also see steam vents, which is where steam and other gases puff out of the ground. You can even find “paint pots” in the park. Paint pots are holes full of bubbling mud that is thick like paint. Sometimes the pots smell like rotten eggs or burnt matches. E. __________ The most famous geyser in the world is Old Faithful and it’s in Yellowstone. It blows its top about every 30 to 90 minutes. It shoots thousands of gallons of hot water high into the air. Visiting Old Faithful is a highlight of any trip to Yellowstone. F. __________ What else can you see in Yellowstone? How about Yellowstone’s own Grand Canyon? It has two big waterfalls and high cliffs of yellow, red, and orange rock. There’s a forest of stone trees in Yellowstone that is millions of years old. The trees were once buried by ash from a volcano and were gradually turned to stone. There are also beautiful lakes, rivers, and mountains to see and enjoy. Yellowstone is rich with wildlife. Hundreds of kinds of birds live in the park, including bald eagles, blue herons, and white pelicans. Yellowstone is home to many large animals. Visitors may see black bears, grizzly bears, moose, bighorn sheep, deer, cougars, herds of elk, and bison (buffalo). Protecting animals in the wild is one of the most important tasks of the park. In fact, the creation of Yellowstone helped save bison from being hunted to extinction in the late 1800s. G. __________ Yellowstone was once home to thousands of gray wolves. But people thought they were dangerous and killed them off. The last wolf in the park was killed in the 1930s. In 1995 and 1996, biologists brought about 30 wolves from Canada and released them inside Yellowstone. Wolf packs soon formed. New pups are born in the park every year. There are now more than 200 wolves in and around the park! Today, seeing a wolf is one of Yellowstone’s big attractions. 10