Grammar

Modal Verb

情态动词有一定的意义，但没有人称和数的变化，不能独立使用，它和后面的动词构成谓语．除 ought 和 have 外，后面只能接不带 to 的不定式。 只作情态动词的 can / could, may / might, 　　　　　　　 ought to, must 可情态可实义的　 need, dare 可情态可助动词的 shall / should, will / would相当于情态动词的 have to, used to

Discovering useful structures Ex. 1: 1. Most ancient festivals would celebrate the end of cold weather… 2. Sometimes celebrations would be held after hunters had caught animals. 3. At that time people would starve if food was difficult to find… 4. …or to satisfy the ancestors, who might return either to help or to do harm. 5. For the Japanese festival Obon, people should go to clean graves… 6. It is now a children’s festival, when they can dress up and go… 7. …the children might play a trick on them.

8. Festivals can also be held to honour famous people. 9. Harvest and Thanksgiving festivals can be very happy events.10. In European countries, people will usually decorate churches and town halls… 11. Some people might win awards for their farm produce… 12. At the Spring Festival in China, people…may give children lucky money in red paper.13. These carnivals might include parades, dancing in the streets… 14. The country… looks as though it might be covered with pink snow.

1. ability, ability, permission, possibility, request

2. permission or request, possibility

3. promise or prediction, past habit, request

4. promise, advice, prediction

5. advice or necessity, guessing, guessing

Ex.2

情态动词 含义 否定式 注意点

can / could

表能力“ 能，会”

can’t

“ 不会，不能”

区别 be able to

表许可“ 可以”

can’t

“ 不可以，不许”

代替 may

表推测“ 可能”

can’t

“ 不可能”主要用于否定、疑问句中1 表示某人通过努力克服困难做成某事 , 要用 was / were able t

o.

2 could, might, would 表委婉语气用于疑问句 , 答语仍须用 can, may, will.

3 can 用于肯定句中 , 可表示”有时可能”

Everyone here can speak English.---Could I have a look at your notebook?---Yes, you can. / No, you can't. It can’t be Mary. She has fallen ill.Can this news be true?Where can they be?She can’t have left school, for her bike is still here.The monkeys look sweet, but they can be very naughty.She can / is able to sing the song in English.I could read when I was four. The fire spread through the hotel quickly but everyone was able to get out.

情态动词 含义 否定式 注 意 点

may /

might

表许可

“ 可

以”

mustn’t

“ 不许，严

禁”

口语中也可用 can’t

表推测

“可

能”

can’t

“ 不可能”

主要用于肯定句，

不能用在疑问句

（ may not 可能

不）

---May I use your pencil?

---Yes, you may. / No, you mustn’t.

She may not be working now.

John might be at home now.

Helen may go on the trip with us, but she isn’t very

sure yet.

She may / might have read it in the paper.

He may not have finished reading the book.

情态动词 用 法

will 表请求( 第二人称 )

表意志 ,

意愿表某种倾向或习惯

would 更客气的请求

过去的意志 , 意愿

过去的倾向或习惯

If you will help me with my English, I will be very happy.

I promised that I would do my best.

Will you tell me something about your hometown?

Would you please speak again more slowly ？

He will always take a walk after supper.

During the vacation he would often visit me.

情态动词 用 法

shall 征求对方意见( 第一 , 三人称 )

表示命令 , 警告 , 威胁或允诺 ( 第二 , 三人称 )

should /

ought to

表示劝告 , 建议 , 命令或责任“ 应该 , 必须”

表示推测 ,

“ 理应 ,

估计 , 大概 , 可望”

should 还可表示“竟然”

Shall we start off now? You shall do as I say.Tell him that he shall have the book tomorrow. You shall be punished if you do that again.You shouldn’t /oughtn’t to smoke so much.She shouldn’t have left without saying a word.It’s five o’clock. John should be at home now. We have prepared a fridge of good and drinks. That ought to be enough for the party.It’s a pity that he should be so rude to a lady.

情态动词 含义 否定式 注意点

must

表必要“ 必须”

needn’t

“ 不必”

( 区别 have to)

有时表“偏要”

表推测“ 一定”

can’t

“ 不可能”

只能用于肯定句，不能用于否定、疑问句

--- Must I finish all assignments at a time?---Yes, you must. / No, you needn't.

I don’t like this TV set. We must buy a new one. There was no more bus. They had to walk home.You must be the new teacher. There is nobody here. They must have all gone home.My MP4 isn’t in my bag. Where can I have put it?

John, look at the time. Must you play the piano at such a late hour?

1. A computer ______ think for itself; it must

be told what to do.

A. can’t B. couldn’t

C. may not D. might not

2. The fire spread through the hotel very quickly

but everyone ______ get out.

A. had to B. would

C. could D. was able to

A

D

4. That big cinema ______ seat 2,000 people.

A. can B. should C. ought to D. is able to

A

5. — Could I borrow your dictionary?

— Yes, of course you _______.

A. might B. will C. can D. should

6. — Might I watch TV after supper?

— Yes, you ________.

A. may B. must C. might D. can

C

A

7. You ______ return the book now. You can

keep it till next week if you like.

A. can’t B. mustn’t C. needn’t D. may not

8. Johnny, you ______ play with the knife, you

______ hurt yourself.

A. won’t ; can’t B. mustn’t ; may

C. shouldn’t ; must D. can’t ; shouldn’t

C

B

9. --Will you stay for lunch?

--Sorry, _____. My brother is coming to see me.

A. I mustn’t B. I can’t

C. I needn’t D. I won’t

10. --May I pick a flower in the garden?

-- ________.

A. No, you needn’t B. Not, please.

C. No, you mustn’t D. No, you won’t

B

C

11. Put on more clothes. You         be feeling cold

with only a shirt on.  A. can  B. could  C. must  D. would

12. "Must I drive to his house and pick up the

children?"  

"No,         ."  A. you shouldn't  B. you might not  

C. you needn't   D. you mustn't

C

C

13. We didn't see Tom at the meeting yesterday.

He         it.  A. mustn't have attended 

B. cannot have attended

  C. needn't have attended 

D. would have not attended

14. We         play chess than bridge. Some of us

don't know how to play bridge.

  A. had better  B. would better 

C. would rather  D. had rather

B

A

15. There is someone knocking at the door.        

it be Tom?

  A. Can  B. Must  C. Should  D. Ought to

16. Two year ago, my husband bought me a bicycle.

If you live in town, it is often faster than a car

and you         worry about parking.

   A. must not   B. may not  

C. should not   D. don't have to

A

D

17.---Is John coming by train? ---He should, but he ____ not. He likes driving his car. A. must B. can C. need D. may

19.---I heard they went skiing in the mountains last winter. ---It ____ true because there was little snow there. A. may not be B. won’t be C. couldn’t be D. mustn’t be

D

C

--- Need he start from the beginning? --- Yes, he must. --- No, he needn’t/doesn’t have to.

1. 作情态动词时 , 仅用于否定或疑问句 , 后接动词原形 , 表“需要”

need

You needn’t return the book now.

2.needn’t have done 表示做了本不必要做的事情 , 意为“本不必要…”Our color TV set is still good enough. You needn’t have bought a new one.

3.Need 作实义动词时 , 表示“需要”，有人称、时态、和数的变化He needs to finish it this evening.

The classroom needs cleaning.

1. 作为情态动词用，常用在否定句和疑问句中。Dare (need) +S +VS + daren’t (needn’t) +V

I daren’t walk through the forest at night.Dare you walk through the forest at night?You needn’t return the book now.Need he go yesterday?

可兼做行为动词的情态动词： need 、 dare

2. 作实义动词用，常用在肯定句中 , 有人称、时态、和数的变化He needs to go there himself.He has grown up,we don’t need to worry about him.

3.Sth (sb) need( want, request)+ doing/ to be done The house needs cleaning/ to be cleaned The boy needs sending to the hospital at once.

句型 时态 动词 情态动词 dare 实义动词 dare 肯定句 现在时 dare do dare/dares to do 过去时 dare do dared to do 否定句 现在时 daren’t/dare not do do/does not dare (to) do 过去时 dared not do did not dare (to) do疑问句 现在时 Dare he do? Do you/Does he dare (to) do? 过去时 Dared he do? Did he dare (to) do

2.I wonder how he____that to the teacher. A. dare to say B. dare saying C.not dare say D.dared say

D

4.As it turned out to be a small house party, we ____ so formally.

A needn’t dress B. didn’t have to dress up

C. Might not have dressed up D. needn’t have dressed up

D

1. 判断正误 :

How dare you say such a thing?

How dare you to say such a thing?

He daren’t to speak English before such a crowd, did he?

He daren’t speak English before such a crowd, dare he?

Nobody need to be afraid of catching the disease.

Nobody need be afraid of catching the disease.

These dishes need be cleaned carefully.

These dishes need to be cleaned carefully.

These dishes need cleaning carefully.

用情态动词完成句子1.You’ve been working all day. You ______ be very tired.2. (The doorbell rings) I wonder who that is. It ______ be Lisa. She’s still in the library at this time.3. It is a long time since we met last time. You ______ come and see us more often.4. I haven’t decided where I’m going for my holidays. I ______ go to Australia.5. –Who was the man talking with your teacher? --I’m not sure. It _______ be her brother.6. When he was there, he ______ go to that coffee shop at the corner after work every day.7. You _____ play the piano while the baby is sleeping.8. Tom, please lend me a hand. My drawer ___ not open

mustcan’t

should

may

mightwould

mustn’twill

• 1 ． The flower is dead. I _______ it yesterday.• A ． should water B ． must water C ． should h

ave watered D ． mustn’t have watered• 2 ． What time ought I _______?• A ． arrived B ． arriving • C ． arrive D ． to arrive• 3 ． He _______ speak to his mother like that.• A ． ought not to B ． doesn’t ought to C ． not

ought to D ． ought to not• 4 ． I don’t think we’d better _______ it any more.• A ． discuss B ． discussing C ． to discuss

D ． discussed• 5 ． You ought to _______ him, but you didn’t.• A ． help B ． helped C ． helping D ． have helped

C

D

A

A

D

1.--Excuse me, but I want to use your computer to type a report.--You ____ have my computer if you don’t take care of it.A. shan’t B. might not C. needn’t D. shouldn’t

A

2. ---When can I come for the photos ? I need them tomorrow afternoon. ---They _____be ready by 12 : 00 . A. can B. should C. might D. need

B

3. With so much work on hand, you ____to see the game last night. A. mustn’t go B. could have goneC. shouldn’t go D. shouldn’t have gone

D

Will /Would you do…? 表请求表意志，愿望，决心would 表过去反复发生得动作或某种倾向 “ 总是 , 总要”used to 表过去常常（现在已没有这种习惯） “ 过去常常”used to 可于状态动词连用　 would 不可以eg. He used to be a quiet boy. ( 　　 )He would be a quiet boy. ( 　　 )

√×

will/would