1. Giới thiệu chung về trợ động từ
Dùng để bổ nghĩa thêm cho động từ chính về tính chất, mức độ, khả năng, hình thái, ... của hành động.
Không thay thế đƣợc cho động từ chính (phải ln có động từ chính đi kèm) Do
Ex: Does Sam write all his own reports? Have
Ex: The secretaries haven‘t written the letters yet. Be
Ex: Terry is writing an e-mail to a client at present.
Động Từ Khuyết Thiếu
Can - Could May - Might Must - Shall
261 Ought to - Should Will - Would Trợ Động Từ Đặc Biệt Need - Dare Have to - Used to
You needn‘t/don‘t need to go now.
Have you to/Do you have to hand it in tomorrow? Dare you/Do you dare to hit me?
I used not to/didn‘t use to wake up late.
2. Chức năng của trợ động từ
2.1. Hình thành thể phủ định bằng cách thêm NOT sau trợ động từ.
do – do not – don‘t does – does not – doesn‘t did – did not – didn‘t is – is not – isn‘t am – am not – amn‘t are – are not – aren‘t have – have not – haven‘t has – has not – hasn‘t had – had not – hadn‘t can – cannot – can‘t
could – could not – couldn‘t may – may not
might – might not must - mustn‘t
shall – shall not – shan‘t
should – should not – shouldn‘t ought to – ought not to – oughtn‘t to will – will not – won‘t
would – would not – wouldn‘t need – needn‘t
dare – dare not (to)
262 used to – didn‘t use to – used not to
Ví dụ:
I have finished my homework.
⟶ have not (haven‘t) finished my homework. They will help us.
⟶ They will not (won‘t) help us.
2.2. Hình thành thể nghi vấn bằng đảo ngữ.
She is cleaning the floor. ⟶ Is she cleaning the floor? He cooked my breakfast. ⟶ Did he cook my breakfast?
Quá khứ đơn Hiện tại đơn Tƣơng lai đơn
+ did do
does will
- didn‘t don‘t
doesn‘t won‘t
? Did S V? Do/Does S V? Will S V?
QKTD HTTD TLTD + was were Am/is are Will be - was not were not Am not/is not
are not won‘t be
? Was/Were S V-ing? Am/is/are S V-ing? Will S be V-ing?
QKHT HTHT TLHT
+ had have/has will have
- hadn‘t have/has not won‗t have
? Had S Vpp? Have/has S Vpp? Will S have Vpp?
QKHTD HTHTTD TLHTTD
+ had been have/has been will have been - Hadn‘t been have/has not been won‘t have been
? Had S been V-ing? Have/has S been V-ing? Will S have been V-ing?
263 Marry doesn‘t love Peter, does she?
Jonny has eaten sugar, hasn‘t he?
2.4. Hình thành câu trả lời ngắn.
Does it take long hours to travel from here to your house? Yes, it does.
No, it doesn‘t.
Mary doesn‘t like fish, neither does Fred. Ms. Phuong works as a teacher.
So do I.
2.5. Được dùng lại trong loại câu tỉnh lược.
You will spend your holidays in Spain. Will you? (= Will you spend your holiday in Spain?) You are dating with that guy. Are you? (= Are you dating with that guy?)