英语----情态动词----推测

must 推测: 肯定是，但不一定是

The tall fellow must be a basketball player. // she can't be a basketball player.

You must think i'm stupid.

He must be playing basketball now.

He must have received my letter. // 时态

//   没有 musn't be 

can 推测

You can't be an artist.

He can't have received my letter.   

 

Can it be ture?

Can he have said so?

 

否定的对比

must be ----->can't be

must have done------> can't/ couldn't have done.

 

may推测

He may know the truth.

He may be waitting for you right now.

He may have got lost.

 

could 的推测

he could have received my package. // 那时候 可能

My book isn't here. Who would have taken it? // 怀疑: 会

He couldn't have done it. He's such a goog man. // 疑问句

 

can 推测

can she have got the book?

She can't have got the book?

He asked to see his exam paper, feeling sure that he couldn't have made(过去的时间 不能反错误) such mistake.

can have done 只能表示从先看过去发生的事情

could have done  表示从过去的看之前的发生的事情

 

推测的程度比较 

肯定：

Must > may> might 

否定： can't>couldn't>may not

疑问句

can>could