I didn't need to clean the windows．My sister did it． e．should／ought to have done表示\应该做的事情没做\，shouldn't／ought not to have done表示\不应该做的事情却做了\。如：

You should have come to the meeting earlier． f．had better+have done用于事后的建议，含轻微责备的口吻，意为\当时最好做了某事\。其否定式had better not

十have done表达相反的含义；如：

You had better have started earlier． g．would rather十have done表示\当时宁愿做了某事\，would rather not have done表达相反含义，两者都含有\后悔\之意。如：

I would rather have refused his offer．

I raised objections at the meeting, but now 1 would

rather not have done that. h. would like to have done would love to have done 表示未曾实现的过去某一打算，含有对曾经的遗憾，意为“本想要去做某事却没做成” 比较:

I would like to have gone to your party, but my mother fell ill and I had to look after her.

I would like to go climbing

this afternoon.

---Why didn’t you come to John’s party?

--- I’d like to have, but I had to look after my sick mother. 10. 易用错的情态动词

a．could／would／might用于疑问句往往表示说话者的委婉语气，而非表示过去时。 Would you lend me a hand? --Could l use your dictionary?一Yes，you can．

--Might l use your pen?--No，