课程介绍
期中考试马上就要到了，多看一些易错题，避免犯同样的错误，也不失为一种很好的考前复习策略呢！
今天总结的高中生在平时英语练习和考试中容易出错的题目是关于情态动词的，情态动词主要考查情态动词本身、否定式和疑问句的含义，以及情态动词+have done的结构。
做情态动词的题目关键在于两点：一是根据语境判断用哪个情态动词;二是看句子时态判断是否需要用情态动词+have done结构。
1.——I thought you wouldn’t mind.
——Well, as a matter of fact I don’t, but you _____ me first.
A. should ask
B. should have asked
C. must ask
D. must have asked
[答案与解析]
选B，should 后接动词完成式表示“本来应该做某事，结果未做”，此处含有责备之意。
2.——I called you yesterday. A woman answered, but I didn’t recognize her voice.
——Oh, it _____ my aunt Jean.
A. must be
B. must have been
C. might be
D. can have been
[答案与解析]
选B，对过去情况的肯定推测，宜用“情态动词 + 动词完成式”，再根据句意，可确定答案为B。注：can 表示推测通常不用于肯定陈述句。
3. That car nearly hit me; I ______.
A. might be killed
B. might have been killed
C. may be killed
D. may been killed
[答案与解析]
选B，表示过去可能发生而实际上未发生的事，用 may /might + 动词完成式.如 He may /might have gone. 他可能已经走了。
4. It’s a very kind offer, but I really _____ accept it.
A. mustn’t
B. needn’t
C. can’t
D. don’t
[答案与解析]
选C。由句意可知。
5. The police still haven’t found her, but they’re doing all they _____.
A. may B. can
C. must D. will
[答案与解析]
选B，do all one can 意为“尽力”或“竭尽全力”。
6. You _____ practise the drums while the baby is sleeping.
A. needn’t
B. mightn’t
C. mustn’t
D. won’t
[答案与解析]
选C，mustn’t 表禁止，不许。
7. You _____ him the news; he knew it already.
A. needn’t tell
B. needn’t have told
C. mightn’t tell
D. mightn’t have told
[答案与解析]
选B，“needn’t + 动词完成式”的意思是：本来不必做某事，但实际上做了。上句意思是“你本来不必告诉他这个消息的，因为他(当时)已经知道了”。注意，句中 knew 为过去式。
8. As she’s not here, I suppose she _____ home.
A. must go
B. must have gone
C. might go
D. might be going
[答案与解析]
选B，must 后接动词完成式表示对过去情况的肯定推测，意为“一定已经做了某事”。
9. Are you still here? You ______ home hours ago.
A. should go
B. should have gone
C. might go
D. may have gone
[答案与解析]
选B，should 后接动词完成式表示“本来应该做某事，结果未做”。
10. I _______ have met him a long time ago. Both his name and face are very familiar.
A. may
B. can
C. would
D. should
[答案与解析]
选A。may have done sth 表示对过去可能发生的事进行推测，意为“可能曾经”。
11. ——Shall we go shopping?
——Sorry, we _______ buy anything now because none of the shops are open.
A. mustn’t
B. needn’t
C. can’t
D. shouldn’t
[答案与解析]
选C。根据上下文的语境推知。can’t 意为“不能”。
12. They often go to the restaurants for meals. They _____ be very poor.
A. mustn’t
B. can’t
C. may not
D. needn’t
[答案与解析]
选B。根据上下文的语境推知。can’t 表推测，意为“一定不”。
13. I didn’t see her in the meeting room this morning. She ______ have spoken at the meeting.
A. mustn’t
B. shouldn’t
C. needn’t
D. couldn’t
[答案与解析]
选D。couldn’t have done sth 表示对过去情况进行推测，意为“过去不可能发生过某情况”。
14. He ______ the test again, in which case, his mother will be very disappointed.
A. might fail
B. must have failed
C. should fail
D. could have failed
[答案与解析]
选A。根据下文的 will be 可知，“他考试再不及格”是将来的事，据此可排除B和D。再根据语意，排除C。
15. ——Why didn’t she come to the meeting yesterday? ——I’m not so sure. She ______ ill.
A. should be
B. should have been
C. must be
D. might have been
[答案与解析]
选D。从时间上看，由于是昨天没来开会，所以推测他生病也应指昨天，故排除A和C。从语境上看，既然上文说 I’m not so sure，那么说明说话者对自己的推测没有很大把握，故选D。
16. Why did you just sit and watch? You _______ me.
A. could help
B. should help
C. could have helped
D. must have helped
[答案与解析]
选C。根据上文的过去时态可知，此句谈的是过去的事，故排除A和C。根据语境排除D。
17. ——You ______ your teacher for help. He is kind-hearted. ——Yes. A whole day _______.
A. can ask, will waste
B. must have asked, had wasted
C. could have asked, was wasted
D. shouldn’t have asked, would be wasted
[答案与解析]
选C。couldn have done sth 表示过去本可以做某事但未做。第二空填 was wasted，陈述的是过去的一事实。
18. ——Is there a flight to London this evening?
——There _______ be. I’ll phone the airport and find it out.
A. must
B. might
C. would
D. can
[答案与解析]
选B。根据下文的 I’ll phone the airport and find it out 可知，说话人对自己的推测没有很大把握，故选 might。若选A，语气太强，不合语境;若选D，不合语法习惯，因为can 表推测通常不用于肯定陈述句中。
19. ——Show me your permit, please.
——Oh, it’s not in my pocket. It ______.
A. might fall out
B. could fall out
C. should have fallen out
D. must have fallen out
[答案与解析]
选D。既然“通行证现在不在口袋里”，那么它“掉出去”应发生在过去，故排除A和B。比较选项C和D所表示的意思，选D更恰当。
20. ——Look at these tracks. It _______ be a wolf.
——Don’t be so sure. I think it _______ be a fox.
A. must; could
B. may; might
C. need; must
D. could; need
[答案与解析]
选A。根据 Don’t be so sure 可知前面一空应填must。第二空填的could表示推测，虽为过去式形式，但表示现在意义，语气较委婉，它与表推测的 can 主要用于否定句和疑问句不同，它可以用于肯定陈述句。
21. ——Did Jim come?
——I don’t know. He _______ while I was out.
A. might have come B. might come
C. mush have come D. should have come
[答案与解析]
选A。根据句中有关时态可知“他来”发生在过去，故排除B;根据 I don’t know 可知选项C语气太肯定，不合适;选项D的意思是“本来应该来而没来”，与语境不合。