情态动词can 和cannot; may和maynot ; must和mustn't 下载本文

Model verbs 情态动词 情态动词本身有一定的词义,但需与动词原形一起使用, 给谓语动词增添情态色彩,表示说话人对有关行为或事物的态度和看法, 认为其可能,应该或必要等。 情态动词后面通常加动词原形。 A1 can and cannot 情态动词can 与cannot 我们用can 表示某人具备某种能力做某事。 如: I can play basketball.

We can finish the work in 20 minutes. 其否定形式为cannot 或can’t . 如: I cannot swim.

I’m afraid I can’t think of more examples to support this argument. 疑问句中, 把can 提到句首, 将can 与主语的位置对调。 Can you speak any foreigner languages ?

— Can you solve this Maths problem ? — I’m sorry, I can’t

A2 may and may not 情态动词may 与may not

在请求对方的许可, 或是准许你做某事时, 常用情态动词may 和can. may 比较正式,can 较常用且更口语化一些。 如:

— May I leave work early today? — 我今天可以早点下班吗? Yes, may — 你可以 — You

No, may not — 你不可以

— Can I open a window ? — 我可以开扇窗吗?

Yes, can — 你可以 — You

No, can’t — 你不可以 You may / can use my dictionary. 你可以用我的词典。 You may not/ cannot use my computer. 你不可以用我的电脑。 A3 must and must not 情态动词 must 与must not

must 用以表示“必须做某事” 或“一定要做某事”, 具有强制性, 表达一种责任或义务或表示很有必要做某事; 或在提出建议时使用, 意为“应该; 得”。 如: We must obey the school rules.

The windows are very dirty. I must clean them.

We must go to the bank today. We haven’t got any money. It’s a fantastic film. You must see it.

must 的否定形式是mustn’t, 表示“禁止”, “决不允许”,具有强制性。 如:

I must hurry, I mustn’t be late. You mustn’t forget to phone Julia.

must 用于一般疑问句中,其肯定和否定回答应引起我们的注意。

— Must I go now ? — 我们现在一定要走吗? Yes, must — 是的; 我们一定要走

— we

No, mustn’t — 不, 我们不可以走。

— Must I finish reading the book this week ? Yes, must — you No, needn’t

典型例析

( ) 1. — _________ your American friend eat with chopsticks ?

—Yes, but he can’t use them well. A. Can B. Should C. Must

【解析】 A 本句表示能力“ 会; 能够”, can 符合题意。

( ) 2. Everyone ________ go through the security check (安检) when entering

the World Expo Park.

A. can B. may C. must D. ought 【解析】 C 本句表示“必须, 一定要”, must 符合题意。

( ) 3. — The winners of the race is a tall and thin boy with glassed.

—Then it _______ be my friend, Mike, who looks very fat. A. might B. can’t C. don’t D. Should

【解析】 B 由上下文语境可知本句的意思是“那么他不可能是我的朋友”, 表推测“不可能”时用“can’t”

( ) 4.— Must I go to the shop with you , Mum?

— Err… I can make it myself, Mike. You ______ go with me.

A. mustn’t B. shouldn’t C. wouldn’t D. needn’t

【解析】 D 由上下文语境可知本句的意思是“ 你没必要去”, 表示“不必要”

可用needn’t 或don’t have to

( ) 5. — This desk is too heavy. I _______ move it. Could you help me ? —

No problem

A. can B. can’t C. should D. shouldn’t 【解析】B 句意为“这桌子太重, 我没法移动它。” 表示“没能力做某事”应

用can’t

( ) 6. — Must I finish my homework right now 、

— No,you _________.

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

【解析】 A 此处must 提问表示“必须” , 否定回答只能用needn’t 或don’t have to .

( ) 7. — ________I take some photos in the hall ?

— No, you __________.

A. Can; needn’t B. Must; mustn’t C. Could; won’t D. May; mustn’t

【解析】D 句意: “ 我可以在大厅里照相吗?” “ 不, 不可以”。 表示请求许可时用can 或may, 其否定回答用can’t 或mustn’t ( ) 8. — _________ I use your ruler, Lingling?

— Sure. Here you are.

A. May B. Would C. Need D. Must

【解析】A 根据句意“用一下你的尺子可以吗?” 可知此处是表示请求许可, 可用may 和can.

考点专练

一 用can , may 或must 的适当形式填空。 1. __________ I ask you a question ? 2. Attending a ball ________ be exciting.

3. Michael _______ be a policeman, for he’s much too short. 4. — Are you coming to Jeff’s party?

— I’m not sure. I _______ go to the concert instead. 5. He never takes a taxi. He _______ be very poor.

6. I thought you ________ like something to read, so I have brought you some books.

7. Look! I __________ stand on my hands.

8. He ______ have been to Shanghai. He knows so well about Shanghai. 9. The play is not interesting. I really _________ go now. 10. She______ like this place. 11. — Could I take this seat, sir? — Yes, you _________.

12. It ________ be very hot in Shengyang in summer.

13. I have just met her in the supermarket. She ______ be in Shanghai now. 14. Mary _________ phone. If she does, could you ask her to ring later? 15. ______ you be happy and healthy. 16. We _______ spit in public.

二 选择正确的情态动

1.Baby _______( can, cannot) run.

2. Dogs _________( can, cannot) understand simple orders. 3词。

1. A b. John practices running every day , so he ___________( can,, cannot) run very fast.

4. You ___________( can, cannot) pass the test if you don’t work hard. 5. Camels ___________( can, cannot) live in the hot areas.

6. Camels ___________( can, cannot) go without water for a long time.

三 根据所给情景,仿照例句写出问句。

1. The radio is very loud, and you and your brother are studying. A: May we turn off the radio? B: Yes, please turn it off.

2. You and your friend see some lost tourists.

A: _____________________________________________________ B: Oh, yes, please help us.

3. You see four of your friends playing basketball.

A: _____________________________________________________ B: Yes, please join us! We need a fifth player.

4. You want to have some ice cream, but you have no money.

A: ______________________________________________________ B: Of course you can borrow 20 yuan.

5. It’s quite hot in the room, and the air conditioner is off.

A: ______________________________________________________ B: Yes, you can turn it off.

6. You ‘d like to order some dishes in a restaurant.

A: ______________________________________________________ B: Yes, of course you can have the menu.

7. You don’t know an English word when you are reading.

A: _____________________________________________________ B: Yes, please use my dictionary.

四 用 you must 或you mustn’t 完成下面的句子。 1. __________________ study hard before your exams.

2. _________________ park your car here. It’s against the rule. 3. _________________ eat more healthy food.

4. ________________ wear a thick coat when it is cold. 5. ________________ swim after a heavy meal.

6. _______________ do some warm –up exercises before going to swim.

五 用适当的情态动词填空。 1. ________I come in ?

2. I _____ speak a little French.

3. _________ I have a look at your pictures? 4. The child ________ ride a bike .

5. The red light is on. We _______ stop. 6. ________ she finish it in three hours?

7. I________ drive a car, but I will learn to drive when I grow up. 8. You ______ borrow three books at a time.

六 用must, mustn’t, may, may not , can 或can’t 填空。