Dear Jack,
I am Li Ning. I got your letter yesterday. From your letter I learn that you didn't pass the exams. I am sorry to hear that. you want me to give your some advice on your studies. I am glad to help you.
First, you must have faith in youself with no fear of difficulties you will meet with. Second, you must have your own way of learning. You should listen attentively to teachers in each class and
take notes carefully. Besides, read more, write more,speak more and ask for more help. Third, what's more, you must keep on it and never give up. If you can do according to my advice, you are sure to succeed. Wish you success!
Yours,
Li Ning