答案：D

题目分析：句意：你昨天可能没有见到汤姆，他上周就去国外度假去了。（1）、“must + have + 过去分词”表示对过去发生的事情或状态进行推测，语气比较坚定，通常只用于肯定句。如：

It must have rained last night, for the ground is wet. 

You must have been mad to speak to the servant. 

（2）、“can / could + have + 过去分词”表示对过去某种情况的怀疑或不确定。can和could一般用于否定句和疑问句，could的语气较can弱。如：

I didn't see her at the meeting this morning; she can't / couldn't have spoken at the meeting.

He can't have finished the work so soon. 

（3）、“may / might + have + 过去分词”表示对已发生的动作或存在的状态进行不肯定的推测，might的语气比may弱一点。这种结构主要用于肯定句和否定句，疑问句改用can或could。如：

They may not have known it beforehand.

You might have read about it in the papers.

（4）、“should / ought to + have + 过去分词”表示过去本该做某事但没做，其否定式表示过去不该做某事但做了，这种句式含有不满或责备之意，ought to的语气比should强一些。如：

You ought to / should have studied harder. 你本应该更努力学习的。（但没有）

He oughtn't to / shouldn't have done that. 他本来就不该做那件事。（可是做了）

点评：情态动词+have done是高中阶段必须掌握的内容，是考生容易混淆的地方，也是考生容易失分的难点，考生应注意这方面的练习。

即学即练：Look at the time! We ______at the theatre ten minutes ago.

A.should have been    B.might have been  C.mustn’t have been D.couldn’t have been

解析：A  句意：瞧都什么时候了! 十分钟前我们就该到戏院了。