Question

I didn't hear the phone. I ________ asleep.

[　　]

A. must be

B. must have been

C. should be

D. should have been

Answer 1

答案：B
提示：

该题考查情态动词. 由于前句使用了一般过去时，所以后句应为对过去发生的行为或状态的推测.表示对过去发生行为或状态的推测，须用“must ＋不定式的完成式.”本句意为“我没有听见电活，我一定睡着了.”例如：You look so sleepy. You must have sat up late last night. 你看上去这么困倦，昨晚一定睡得很晚. The ground is very wet, it must have rained yesterday. 地很湿，昨天一定下雨了.