请问, 这两种英语虚拟语句有何区别??

来源：百度知道 编辑：UC知道 时间：2024/05/29 11:59:14
must have done
could have done
都表示都对去所发生事情的猜测, 但他们有何区别呢?

前者比后者肯定的程度大得多
must have done一定已经做了某事
could have done可能已经做了某事
for example
Jim said he saw Lucy in the library,so Lucy must havn left the classroom.
Lucy was not in the classroom, I think she could have went to the toilet.

understand?

must的语气较could更肯定一些~~~

must强烈的感觉到，很确定
could大概发生了