请告诉我must have been,could have been,should have been,would have been和need have been的意思和用法
，在下不胜感激

1、must have done:表示对过去情况的肯定猜测，必须用于肯定句，如果用于否定句或疑问句，要用can/could have done.
例如：He must have gone out,because the room was dark
She could not have passed the exam,for she was sick
2、could have done : 有两个意思：第一个就是对过去情况的猜测，只能用于否定句或者疑问句中，就提的例子可以看上边；第二个意思:本来能够做而没有做某事，用于肯定句，例如：I could have stayed with you ,but I was busy.
3、should have done :本来应该做而没有做某事，例如：I should have cleared the room, but I forgot
4、need have done: 本来需要做而没有做某事，例如：You need have finished it,but you failed
5、would have done: 表示虚拟语气，是对过去情况的虚拟，一般跟if 条件句连用。例如：
If I had known your number, I would have called you