1. 根据句意及汉语提示完成单词。

1. （1） Some African countries are (开发)rainforests for wood.

3. （2） Tom，who is my (同事)，works in the same office with me.

5. （3） They were(围起来)immediately by small boys wearing school caps.

7. （4） He built up wealth by(做生意)with other countries.

9. （5） It's almost impossible to find him in the (巨大的)ocean.

11. （6） This hill is too(陡峭的)to ride up on a bicycle.

13. （7） Just smile (自然地)while I take your photo.