1. 用适当的介词填空（可重复选择）

as；at；against；to

1. （1） The approach the house was by a minor road.

3. （2） The man represented himself be a friend of the President.

5. （3） All the high school students are their crossroads, so they should work hard.

7. （4） The policeman can defend himself knife attacks.

9. （5） I must limit my living expenses500 dollars a month.