2013高考英语语法最后30天精讲精练
情态动词
1、情态动词 + have done sth
这个结构有着特殊意义：用来表示猜测（设想可能发生过什么事情）或
想象（设想可能出现过什么不同的情况）
①should (ought to) have done sth 本来该做而未做
This wall oughtn’t to have been painted blue.
②need have done sth 本来有必要做而未做
You needn’t have told her the news.
③must have done sth 对过去所做动作的肯定推测
---We went to Paris. ---That must have been nice.
④can have done sth 对过去所做动作的否定或疑问推测
I don’t think he can have heard you. Call again.
Where can John have put the matches?
⑤may (might) have done sth 过去可能发生某事，与could相比，may和
