根据下列短文，写出与各小题所给汉语相对应的英语单词（每空一词）。

    As we all know, the environment around us is getting worse and worse. Some chemical factories always pour(废弃的) water into the(河流). And they also(产生) terrible gas. In some places, some people even have no clean water to drink. So I think we must do something to protect the environment.

    How to protect the environment? First, as a student, we should use cloth bags instead of (塑料的) bags when we go shopping. (第二), we'd better reuse the old textbooks as possible as we can. Third, we should never forget to turn off the lights when we leave the classrooms. In a word, we must try our best to protect our environment. I believe we can make the world a better place to live in.