must have done的用法

包括四种常用用法，must have done sth.、can/could have done sth.、can't/couldn't have done sth.、ought to/should have done sth.。

一、must have done sth.一定做某事。表示对过去事情的较有把握的推测，这时只能用在肯定句中，“肯定/必须已经干过…”，在否定句和疑问句中用can't或couldn't或can/ could，例如：

1. From what you said, she must have told you all about it.

从你的话看，她一定告诉了你所有的事情。

2.The light was out. They must have gone to bed.

灯都熄了，他们必定睡了。

3.He must have done it when I was off with those assholes.

他一定是趁我和那群混蛋一起的时候做的。

4.The man must have done something right, more right than all jumpers before.

这个人一定是做了些很对的事，比所有以前跳高的做得更对。

5.China must have done something supremely right to produce the economic miracle we observe.

中国一定是做了非常对的事才产生了我们见到的经济奇迹。

6.You must have done something to her.

你一定有跟她做什么事。

二、can/could have done sth.本来能够做某事，而实际上未做。

1. But we could have done it all so much better.

但是，我们本可以把这一切做得更好。

2.If you do a go