Dear Yang Xi
I got your letter just now.I am very sorry to hear that you've got bad grade in your English. You lose your confidence and want to give it up. English is one of the most important subjects at school and it is spoken by more than a billion people in the world. English nowadays is widely used in science, business, the media and popular culture so we should learn it well. Leaning English takes time. So you should study hard and spend lots of time on it. Why not ask your teacher and classmates for help when you have any difficulties in learning English. If you learn English by heart, I am sure you will learn it better. Good luck to you.
Yours
Zhang Tao