He must have been very nervous when speaking. Did you _______ that his hand was shaking?
                    举一反三
- You when you heard the news。 A: must be very excited B: must have been very excited C: can be very excited D: will have been very excited
 - He did not attend the meeting yesterday. He______ill. A: must be B: must have been C: should be D: should have been
 - When someone offers you a handshake, you must shake his/her hand limply.
 - He must have been very depressed when he heard the news, A: mustn't he B: haven't he C: wasn't he D: didn't he
 - He did very badly on the exam. He ______ harder. A: must study B: must have studied C: should study D: should have studied
 
