英语 情态动词
You____ do i if you really don't want to .
A.mustn't B.can't C.needn't D.shouldn't
People ______ breathe when they are under water.
A.can't B.mustn't C.shouldn't D.needn't
There's somebody at the door .Who ______ it be Is it the postman?
No,it ____ be him.It's just seven o'clock.It's too early.
A.may;can't B.will;won;t C.may ;mustn't D.must; may not
The boy said he had to speak English in class,but he ____ speak it after class.
A.could B.didn't have to C.might D.shouldn't