仔细阅读下面的短文，短文中有10个空格或划线句子。请按照每小题括号内的具体要求完成语法填空、词形变化、句子合并、句子改写以及病句改正等。答案填写在标号为1～10的对应位置。

　　Pollution 　　1　　(be)a problem that happens in water, air and earth．It is 　　2　　(表语)with animals and humans．The water pollution is 　　3　　(cause)by waste from factories．The 　　4　　(fish)will die, if the river polluted by chemical factories．Then if some people 　　5　　(谓语动词)those fish, they will also be dead．The others is air pollution．　　6　　(改正错误)It comes from factories, power stations and cars．　　7　　(冠词)chemical in the smoke will fall in the rain．This “chemical rain” will kill trees and fish．It’s either bad to the building．　　8　　(改正错误)From that we 　　9　　(情态动词)know how bad the pollution is．

　　We hope that the scientists can find out the way to make environment better soon．　　10　　(改为形式主语结构)