全世界的环境问题在变得越来越严重。请你根据漫画内容和下面要求给China Daily写一封信反映这一情况，并提出保护环境的建议。关于环保的建议信
注意：1.信的开头与结尾已经给出，不计算在总词数内。
2. 字数要求: 120左右。
人口膨胀population expansion;过度开发overdevelopment。
Dear editor,
Environmental problems are being more and more serious all over the ing more and more serious all over the e less and less. Trees on the hills have been cut down, and waste water is being poured continuously into rivers. The whole ecological balance of the earth is changing. Massive destruction of environment has brought about negative effects and even poses a great threat to man's existence.
We must face the situation that exists and take actions to solve our environmental problems. We hope that all these measures will be effective and bring back a healthful environment.
Yours truly
Li Hua