What ________ you ________ when I called you, Jack?

1. A.
   are; doing
2. B.
   did; do
3. C.
   were; doing
4. D.
   was; doing

请根据句意从方框中选择合适的动词，并用其适当时态填空，使句子通顺。

【小题1】It was raining heavily when he ________ home last night.
【小题2】Mary wonders what she _________ as when she grows up.
【小题3】— Amy, I called you yesterday evening, but nobody answered the phone.
— Oh, I ________ a walk with my mother at that time.
【小题4】—________ you ________ a letter to your mother recently?
—Yes, I wrote one last Sunday.
【小题5】We are told that sound ___________ through air at a speed of about 340 metres per second.

补全对话（5分）
根据下面的对话情景，在每个空白处填上一个适当的句子，使对话意义连贯，完整。
(Michael and Kangkang meet at the school gate.)
A: Hello, Kangkang.
B: Hi, Michael.
A: I called you just before I left home ,but you were not in. 【小题1】__________________________
B: Oh, sorry. I’ve been to the library.
A: What did you go there for?
B: 【小题2】__________________________________________________________
A: Well,【小题3】_____________________________________________________
B: It’s about 1.3 billion, one fifth of the world’s.
A: Has the government done anything to control the huge population yet?
B: Yes.【小题4】_________________________________________________and it has worked well in controlling the population growth for many years.
A: Really? However, the population problem is still serious in China, isn’t it?
B: Yes, it is. Oh!【小题5】_________________________________________Let’s go to the classroom.
Hurry. Let’s go.
A.A. What’s the population of China?
B.B. Where have you been?
C.C.What’s wrong?
D.D. The government has carries out the one-child policy.
E.E. There goes the bell.
F.F. I went there to look up some information about China’s population.
G.G.I borrowed some story books.