情态动词表推测专项练习题

1. Look! The light is out in her room. She ———— to bed already.

A. must go

B. had to go

C.must have gone

D.has gone

2. ─There were already five people in the car but they managed to take me as well.

─ It______ a comfortable journey.

A. can't be

B. shouldn't be

C. mustn't have been

D. couldn't have been

3. My sister met him at the Grand Theatre yesterday afternoon, so he ___ your lecture.

A. couldn't have attended

B. needn't have attended

C. mustn't have attended

D. shouldn't have attended

4. You ______ be tired - you've only been working for an hour.

A. must not

B. won' t

C. can' t

D. may not

5. - Isn' t that Ann's husband over there?

- No, it _______ be him -I'm sure he doesn't wear glasses.

A. can't

B. must not

C. won't

D. may not

6. I was on the highway when this car went past followed by a police car. They

______ at lease 150 km an hour.

A. should have been doing

B. must have been doing

C. could have done

D. would have done

7. 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

8. This cake is very sweet. You __________ a lot of sugar in it.

A．should put B．could have put C．might put D．must have put 9.—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

情态动词must, can, could, may, might 表推测的用法

情态动词中的must, can, could, may, might都表推测。其中must的可能性最大，can / could次之，may / might最小。具体用法如下：

1.must的用法

（1）表示推测“可能性”时，意思是“一定、准是”，语气较肯定，较有把握He must be American. = It is certain that he is American. 他准是个美国人。

（2）must表推测只能用于肯定句。如果要表示“一定不、肯定不”的意思时，应用can`t,如询问某种可能时，应用can。

He must know my address. 他肯定知道我的地址。（一定）

He can`t know my address. 他肯定不知道我的地址。（一定不）

Can he know my address? 他知道我的地址吗？（询问可能性）

（3）must表示推测时，可以推测现在/正在发生的动作/过去发生的动作。

He must have a car now. （现在）他一定有辆小汽车。

He must be doing his exercises in the classroom.（正在进行）他一定在教室里做练习。

He must have finished the work.（过去发生）他一定已完成了工作。

注：must表示推测时很少用于将来的情况。一般不用He must come tomorrow.可用It`s certain / I`m sure that he will come tomorrow.

（4）在反意疑问句中，当附属部分含有表示推测意义的must时，疑问部分的助动词应与must后面的动词在非推测情况下的用法保持一致。

He must be a worker, isn`t he? （现在）他准时个工人，是吗？

It must have rained last night, didn`t it? （过去）昨晚一定下雨了，是不是？

You must have learned English for many years, haven`t you? （完成时）你一定学了好多年英语，是吗？

2.can / could的用法

（1）can表示推测“可能性”时，往往用于否定句或疑问句。Can`t“一定不”，语气很肯定。can在疑问句中意思是“会、可能”。

He can`t be at home. = It is impossible that he is at home. 他一定不在家。

（2）can /can`t后可接进行时/完成时，表示对现在发生的动作或过去发生的动作进行推测。

They can`t be reading in the library. 他们一定不在图书馆读书。

He can`t have gone to Shanghai for I saw him a minute ago.

他不可能去了上海，我刚才还看见他。

It`s so late. Where can she have gone? 天晚了，她可能去哪儿了呢？（3）在反意疑问句中，当陈述部分含有表示推测意义的can`t时，疑问部分的助动词应与can`t后面的动词在非推测情况下的用法保持一致.

He can`t be a teacher, is he? 他不是教师，是吗？

She can`t have finished her homework, has she?

她一定没有完成家庭作业，是不是？