One possible version ：
Dear Wang Lin,
Glad to hear from you .I’d like to give you some advice on what to do as the first round revision is coming.
Firstly ,make a practical plan ,which will help you have a clear aim .Secondly ,make certain that all subjects to be examined in go in a balanced way, especially pay more attention to your English study.Thirdly and the most important is that you must follow your teachers’ advice.Lastly ,find time to take some exercise every day,and don’t stay up too late so as to keep fit .Meanwhile ,try to be relaxed. Thus you can study in high spirits.
I hope this will be of some help to you . Best wishes
Yours Sincerely,
Li Hua
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