情态动词+ have +过去分词的几种用法

Have既可作助词，也可作及物动词和名词使用。情态动词+ have +过去分词（即情态动词+完成式）是常见的一种动词结构，也是初高中常考的语法。

情态动词+ have +过去分词的几种用法：

（1）may(might)have + done sth, can (could) have + done sth表示过去，推测过去时间里可能发生的事情。

Philip may (might) have been hurt seriously in the car accident.

Philip can(could) have been hurt seriously in the car accident.

（2）must have+done sth，对过去时间里可能发生的事情的推测，语气较强，具有“肯定”，“谅必”的意思。

Linda has goneto work, but her bicycle is still here.——She must have goneby bus.

（3）ought tohave done sth, should have done sth

本应该做某事，而事实上并没有做。否定句表示“不该做某事而做了”。

You ought to (should) have been more careful in this experiment.

He ought not to have thrown the old clothes away.（事实上已扔了。）

ought to 在语气上比should 要强。

（4）needn't havedone sth　本没必要做某事

I dressed verywarmly for the trip, but I needn't have done so. The weather was hot.

（5）would liketo have done sth本打算做某事

I would like to have read the article, but I was very busy then.