7.In big cities , cars and buses have 　　　　　　　　　(污染) the air.

6.Some people have cut down too many tress . I t is a bad 　　　　　　　　　(举止) .

5.Trees can stop the wind from 　　　　　　　　(吹)the earth away .

4. Many people don’t pay attention to 　　　　　　　　　(保护)nature .

3.If people spit something in public , they should be 　　　　　　　　　(处罚).

2.Each year people pour much 　　　　　　　　　(废物) into rivers , lakes and so on .

1. In some cities , vehicles 　　　　　　　　(产生)too much noise .

10. I have been to an English　　　　　　　 　(培训)school to improve my English .

第十七组

9.Poject Hope is a social 　　　　　　　　　(服务)program to help peopole.

8.The government 　　　　　　　　(提供) homeless people with nice homes.