Dear John,
I'm sorry to hear that you are so addicted to online games that it has greatly affected your physical health. To help you get rid of it, I'm willing to give you some advice.
First, you should take control of the time spent on online games. Meanwhile, pay more attention to other things, such as taking part in more activities. Besides, forming a regular habit of getting up and going to bed can also help you to change for the better. As Gandhi said, “Be the change you want to see in the world.” As long as you make up your mind with a little self-discipline, any bad habit can be kicked. In this way, your health and quality of life will be largely improved.
I hope that you can keep away from online games and live a healthy and dynamic life.
Yours sincerely,
Li Hua

Dear readers, 
It goes without saying that no pleasure can be tasted by a man without health. Health is far more important than anything else. Good health enables us to enjoy our life and achieve what we hope for in our career.
How can we keep healthy? Here are some suggestions for you to follow.
To begin with, we should develop good habits. We should avoid food with lots of sugar and fat. What's more, we have to get rid of those habits that damage our health, such as drinking and smoking. Last but not least, we'd better exercise every day to make our bodies strong. Proper diet and enough exercise do good to our health.
If we follow the advice given above, we will lead a healthy life.
Yours sincerely, 
Mr. Helper