“情态动词＋have done”表示对过去情况的推测或估计，是历年高考的热点。现就这一语言现象作如下归纳：

1. should （ought to） have＋过去分词

表示过去应该做而（实际）没有做的事情，含有责备或遗憾的语气，意为“本应该……”；其否定形式为“should not／ought not to have ＋ 过去分词”，表示某种行为不该发生但却发生了。

Mr. White _____ at 8：30 for the meeting ， but he didn‘t’ show up.     （04‘广西卷）
A. should have arrived
B. should arrive
C. should have had arrived
D. should be arriving
[解析]本题中的一个关键词but暗示了“Mr. White按道理理应到了，而他没有到”。故答案选[A].

2.needn't have＋过去分词

表示过去没有必要做某事， 但实际上做了某事。

As you worked late yesterday， you_________ have come this morning.      （06‘陕西卷）
A. mayn‘t          B. can’t        
C. mustn‘t        D. needn’t
[解析] He needn't have come，表示“他本没有必要来（实际却来了）”，根据句意，答案应选[D].
[注意] He didn't need to come yesterday，意为“他昨天没有必要来（实际也没来）”。

3.must have＋过去分词

用于肯定句，表示“过去一定做过某事”，表示一种很有把握的推测。
[注意] 对过去发生情况的否定推测常用can‘t／couldn’t have ＋过去分词。

I have lost one of my gloves. I ________ it somewhere .         （05‘北京春季）
A. must drop             
B. must have dropped
C. must be dropping      
D. must have been dropped
[解析]本题应选B.本题的前一句说明一个结果，后一句则表示一个原因。
I _______have been more than six years old when the accident happened. （05‘天津卷）
A. shouldn't          B. couldn't        
C. mustn't       D. needn't
[解析]从题意上分析，本题的前一句陈述一个理由，后一句则是由前一句得出的结论。故本题选[B] .

4.may／might have＋过去分词

表示对过去情况的一种不太有把握的可能性推测，表示“过去可能／大概已做了某事”；否定句表示“过去可能还没有做某事”。

We _______ have proved great adventurers， but we have done the greatest march ever made in the past ten years.                                          （06‘天津卷）
A. needn‘t      B. may not      
C. shouldn’t          D. mustn‘t   
Key：[B]

5.can／could have＋过去分词

表示“过去本来可以做某事，但实际上没有做”；否定句表示“不可能已做了某事”；疑问句表示“可能／也许已做了某事吗？”。

—— I stayed at a hotel while in New York .
—— Oh， did you？ You ＿＿＿＿ with Barbara.                      （NMET‘98）
A. could have stayed       B. could stay
C. would stay             D. must have stayed                Key： [A]

巩固性练习：从A、B、C、D中选择最佳答案。
1.——You didn‘t wait for Mr. Smith last night， did you？
——No， but we ______. He didn‘t return home at all.
A. couldn‘t have waited          B. needn’t have
C. didn‘t need to               D. should wait
2.Harry ______ have won the Physics competition easily yesterday， but he gave up.
A. could   B. might   C. should   D. must
3.——May I speak to your manager Mr. Smith at six o‘clock tonight ？“
——“I‘m sorry， Mr. Smith         to a conference before then.”
A. will have gone                 B. had gone    
C. would have gone                 D. has gone
   4.——Tom took away our teacher‘s cell phone without being permitted.
—— Really？ I can‘t imagine that he _______ have done such a thing.
A. must               B. may             
C. can                D. should
5.—— Was it you that made the suggestion？
—— It        have been. I can‘t remember.
A. need                 B. must               
C. should                 D. may
6.The weather turned out to be fine yesterday. I_________ the trouble to carry my umbrella with me .
A. should have taken             B. could have taken
C. needn't have taken            D. mustn't have taken
7.He paid for a seat， when he ______ have entered free.
A. could                            B. would                        
C. must                     D. need
8.I didn‘t see her in the meeting room this morning. She       at the meeting .
A. mustn‘t have spoken    B. mightn’t have spoken
C. can‘t have spoken        D. shouldn’t have spoken
9.—— Hi， is that Peter Brown？
——Sorry. You ______ the wrong number .
A. must dial                            B. must have dialed     
C. should dial                           D. should have dialed
10.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

Keys for reference： 1——5 CAADD      6——10 CACBB