1. 用方框中所给单词的适当形式填空。

future    pollute     planet    plant    part

1. （1） —Don't throw(扔) dirty things into the river. They willthe river.

   —I'm sorry.

3. （2） I wonder if there is life on other.
5. （3） need light and water to grow.
7. （4） I think people will have less work to do in the.
9. （5） Everyone should play ain cleaning the park.