Dear editor, 

I am a faithful reader of your newspaper and appreciate the positive action that you are always widely promoting environmental awareness by the newspaper. However, the present situation of the environment is still tremendously bad. I hope ("believe that" is correct, but sounds domineering) you will take it seriously.

In my humble (1) opinion, environmental woes can improve only when the public is more deeply aware of the importance of environment protection. There are at least three methods to assuage this problem. Firstly, it is widely that an environmental group should promote the significance of environmental awareness. Secondly, the government should play an active role in it. That is to say, for example, they should punish those who harm the environment. What's more, all the sectors should implement supervision and control system on each other.

Since my voice alone is too weak to be heard, I hope you can call on the public to adopt environmental conservation.

Yours sincerely,
Li Ming

(1) Although "in my humble opinion" is an English phrase, it is often seen as puerile, duplicitous, and especially proud. It is often used when people want to make a statement, but can't defend their argument (or have already lost an argument). Instead, the plain "in my opinion" is preferred. In academic writing, "in my opinion" should not be used.