1. 用所给词的适当形式填空

1. （1） The computer is one of the most useful (tool) in our daily life.

3. （2） You must finish (do) your homework first.

5. （3） We can make things with the (sand).

7. （4） The girl (name) Lily is Lucy's sister.

9. （5） —Shall I tell Tom the good news?
   

   —No, you needn't. I (tell) him already.
   

11. （6） —How long you (live) in the village?
    

    —For about twelve years.
    

13. （7） The boy often puts his (foot) in the water to keep cool in hot weather.