党校结业论文情态动词can 和cannot; may和maynot ; must和mustn't

2021年1月12日发(作者：乔维怡)
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
_______( 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。
This is Mrs Lee’s first trip to Canada. She (1) _____________ only speak a little
French and a little English . Today, she will go the Canadian Embassy to get visas for the
family. She knows she (2) ___________ forget to take all the family’s passports with her
or they will not get visas. She (3) _______________ get there before the embassy closes.
Dean has just bought three pairs of skis. He is trying , but he (4)
_________________ carry them all at the same time. He wants to take a taxi home, but
the taxis won’t stop for him. He (5) _________________ find a taxi queue if he wants a
taxi.