must的用法及练习

情态动词must 的用法

1.must 表示必要性，“必须”（肯定句，疑问句常见）

①You must go to bed now.

②Must I start at once?

2.否定式mustn’t 表示“禁止”

①You mustn’t smoke here.

②We mustn’t be late again. (不许我们再迟到了)

3.由must 引导一般疑问句时，肯定回答用must，否定回答用needn’t

或don’t have to.

---- Must I stay at home?

---- Yes, you must. / No, you needn’t

4.当出现反问句式时，如果其陈述部分must 表示“必须，有必要”

时，反问句用needn’t，如果其陈述部分mustn’t 表示“禁止”，反问句用must.

①----You must go there, needn’t you?

---- Yes, I must. / No, I needn’t/don’t have to.

②You mustn’t go there, must you?

5.must 表示推测时，有3种形式时，反问句与must 后的动词保持

一致。

⑴对现在的动作进行推测

①You must be hungry now, aren’t you?

②You must have the wrong number. There is no such person, haven’t/

don’t you?

⑵对正在进行的动作进行推测

He must be doing his homework, isn’t he？

⑶对过去发生的动作进行推测

①You must have read this book, haven’t you?

②It must have snowed yesterday, didn’t you?

6.must 用于反语，表示劝诫。

-----Must you make so much noise?(你非得吵这么大声吗？)

-----Sorry, I’ll try not to.

（2005全国Ⅲ卷）John, look at the time, __A__ you play the piano at such a later hour? A. must B. can C. may D. need

7.与说话人的愿望相反，“偏偏，偏巧”。

①I don’t want to be late, but my car must break down on half way.

(2004 天津)

②----Who is standing over there?

----well, if you __C____ know, the girl is Marry.

A. may

B. can

C. must

D. shall

③Why must it rain on Sunday?

8.must not (always) be doing. “不应该，一定不要”. always 加重不

赞成的语气。

①You mustn’t always be talking so much.

②When you learn a foreign language, you mustn’t always be translating

everything into your own.

Must用法专练

一、单选

1.John, look at the time. ______ you play the piano at such a late hour? (2005)

A. Must

B. Can

C. May

D. Need

2. He _____ have completed his work; otherwise, he wouldn’t be enjoying himself by the seaside.

A. should

B. must

C. wouldn’t

D. can’t

3.I was on the highway when this car went past followed by a police car. They ______ at least 150 kilometers an hour.

A. should have been doing

B. must have been doing

C. could have done

D. would have done

4. ----Tom is never late for work. Why is he absent today?

----Something _____ to him.

A. must happen

B. should have happened

C. could have happened

D. must have happened

5.This cake is very sweet. You ______ a lot of sugar in it.

A. should

B. could have put

C. might put

D. must have put

6. According to the local regulations, anyone who intends to get a driver’s license______ take an eye test.

A. can

B. must

C. would

D. may

7. ----- Must he come to sign this paper himself?

---- Yes, he ______.

A. need

B. must

C. may

D. will

8. ----- May I smoke here?

---- If you _____, choose a seat in the smoking section.

A. should

B. could

C. may

D. must

9. In crowded places like airports and railway stations, you _____ take care of your