题目内容：

must have done 和must have been 的区别
都是对过去的猜测,二者的区别是什么?

优质解答

其实就是be动词与do动词的区别,该用哪个与must无关；你可以考虑现在完成时、一般现在时、一般过去时该用哪个,照此办理
It must have rained last night.昨晚肯定下过雨.
You must have been tired after all this work.