Our environment is becoming worse and worse day by day. Now we can’t see blue sky in the cities in the daytime. There is no fish in the dirty rivers or lakes. Even worse, a lot of people can’t drink clean water. It’s time for us to do something to protect the environment. As a student, we should ride a bike or walk to school every day. We shouldn’t pour waste water into rivers. And don’t throw rubbish here and there. If everyone makes contribution to the environment, it will get cleaner and tidier soon.

题目分析：这是一篇给材料作文，在写作时要审清题目，理清结构。文章可分为两部分：列举污染现象；保护环境建议。在写作时要把材料中的要点看清，并用正确完整的句子表达清楚；句子之间注意衔接，可使用一些引导性的句子和连词，使文章更紧凑连贯。

【亮点说明】

这篇文章条理清晰，句子完整，使用了很多短语何句式，如There is…有…; a lot of许多；It’s time for us to do…是我们做……的时候了；As a student作为一个学生；makes contribution to为……做贡献，等等。另外使用了一些连词或短语，如Even worse,更糟糕的是，If引导的条件状语从句等，使文章更紧凑，逻辑更清晰。