从A、B、C、D中选出可以填入空白处的最佳答案。

　　1. John ________ a better job, but he was too careless.

　　A. should do B. must have done

　　C. could do D. could have done

　　2.─I don't know why he is late.

　　─Nor do I. He ________ have had an accident.

　　A. can B. shouldC. mightD. must

　　3. The playground is all wet. It ________ rained last night.

　　A. had B. can have

　　C. should have D. must have

　　4. It's already eleven o'clock. He ________ to bed.

　　A. must have gone B. must go

　　C. should have gone D. can't have gone

　　5.─Who told you my address?

　　─I don't remember clearly. It ________ Tom.

　　─It ________ Tom. He doesn't know it.

　　A. may have been; can't be

　　B. can be; mustn't be

　　C. must have been; can't have been

　　D. may have been; mustn't have been

　　6. John passed the exam. He didn't study very hard. The exam ________ difficult.

　　A. can't have been B. must have been

　　C. couldn't be D. might have been

　　7. We ________ have hurried. We had to wait twenty minutes before the meeting began.

　　A. needn't B. should C. must D. couldn't

　　8.─Mary looks sad. Did you tell her about the accident?

　　─Yes, but I ________ have told her.

　　A. should B. shouldn't

　　C. must D. ought to not

　　9. She ________ have gone to college, but she didn't pass the exam.

　　A. might B. wouldC. must D. need

　　10. He must have seen the inspector last night, ________ he?

　　A. mustn't B. hasn't C. didn't D. doesn't

　　【答案与简析】

　　1. D。根据后面的but he was too careless，说明约翰的工作本来可以做得更好(表示一种可能性)，但是他太粗心了；如果用B:约翰的工作肯定做得更好，但是他太粗心了。不合逻辑。

　　2. C。由Nor do I可知，说话者对他为何迟到没有把握。指没有把握的推测一般用may/might＋have＋过去分词表示，而can＋have＋过去分词一般用于否定句或疑问句，故可排除A。

　　3. D。备选项B常用于否定句或疑问句，故可排除；备选项C通常有责备的语气，在此不合题意；备选项D表示一种有把握的推测，符合The playground is all wet这一前提。

　　4. A。由前句的"现在已经十一点钟了"，说明现在很晚了，故备选项A (他肯定已经睡觉了)符合题意；而备选项D(他不可能已经睡觉了)和备选项C(他本来已经睡觉了)均不合题意。

　　5. A。由I don't remember clearly可以看出，说话者对所发生的事情不太有把握，故第一空用may have been表示不肯定的推测；由He doesn't know it可知,该说话者对前一位的推测予以否定，故第二空填can't be，表示"不可能"。must表示推测时一般用于肯定句，故可排除D。

　　6. A。既然约翰学习不是很努力，也能通过考试，说明那次考试"不可能很难"，故选A符合题意。

　　7. A。我们到达开会的地方等了二十分钟才开始开会，说明我们来开会的时候匆忙是"不必要的"，故选A。needn't have done sth.表示过去不必做某事(但做了)。

　　8. B。玛丽现在很悲伤，是因为我把那次事故告诉了她；如果我当时没有告诉她，她现在就不会悲伤了。言外之意是：我当时不该告诉她那次事故。指过去不该做某事(但却做了)，常用should not/ought not to＋have＋过去分词表示。

　　9. B。她本来可以上大学的，但她没有通过考试。would＋have＋过去分词表示过去本来要做某事，却因某种原因而未做成。

　　10. C。含must have done句式的反意疑问句，若陈述部分含表示过去时间的状语,反意疑问部分用过去式。本题有过去时间状语last night，故选C。

　　(文/刘石才；高中一年级版03～04学年第34期；版权归英语辅导报社所有，独家网络合作伙伴新浪教育，未经许可，不得以任何形式进行转载。)