如下:
Dear Chris,
I'm glad to receive your letter.You asked me how to learn Chinese well.Here's some advice for you.I think it's important to take Chinese classes.
You'll find it helpful.As we know,"Use it or lose it."So practicing in groups is pretty necessary.What's more,you could improve your Chinese by watching Chinese movies.
It is also a good idea to learn and sing Chinese songs.You'll learn more Chinese words by doing that.If possible,you can even make some Chinese friends.
They will be pleased to help you and it's a good chance for you to learn more about Chinese culture.(方法)
Learning is a lifelong journey.Keep practicing every day,then it will bring something new.
Best wishes!
Yours。
David 。