4. I began to fall over my own feet. Down　 _____ again and again.

　 A. I went　　 B. did I go　　 C. went I　　 D. I did go

3. Not only ____ polluted but _____ crowded.

　 A. was the city; were the streets　　　 B. the city was; were the streets

　 C. the city was; the streets were　　　 D. was the city; the streets were

2. The door opened, _______.

　 A. came in a pretty girl in　　　 B. in came a pretty girl

　 C. came a pretty girl in　　　　 D. in a pretty girl came

1.　　 Not until all the fish died in the river ____ how serious the pollution was.

　 A. the villagers realize　　　　 B. did the villagers realize　　

C. didn’t the villagers realize　 D. the villagers did realize

10. 他一生致力于研究英语语法。

He ____ _____ ____ ____ _____ English grammar.

9. 这里所有的人，包括老人，都参加了抗洪斗争。

Everyone here ____ ____ ____ the fight _____　 the flood, _____ _____ ____.

8. 不论困难多大，他决心去尝试一下这个实验。

____ _____ ____ ____ it is, he ____ _____ _____ _____ ____ ____ at the experiment.

7. 三兄弟轮流照顾生病的妈妈。

The three brothers ___　 _____ ____ ____ _____ their sick mother.

6. 那是我们无法忍受的，所以便决定到户外去游戏了。

That was ____ _____ we could _____, so we _____ ____ ____ ____ outdoors.

5. 他远游到西藏，并了解了西藏人的文化。

He ____　 ____ ____ ____ Tibet and ___ _____ the _____ of the Tibetans.