动词填空。

1. All of the boys must______ (be) here before seven o'clock?

2. Life______ (be) a good teacher.It has taught me how ______ (think)

3.—Who ______ (knock) at the door?

   —I ______ (not know).Let me go and see.

4. I'm glad ______ (hear) that you ______ (pass) the exam already.

5.Would you like something ______ (eat)?

夏季风强的年份，亚洲东部和南部可能出现的灾害天气是 [ ]

A、霜冻

B、旱灾

C、涝灾

D、焚风