One possible version:
I am Li Ming of Senior Three, Guangming Middle School．I am writing to tell you about some symptoms of anxiety among us students before exams．
Most of us feel nervous whenever we’re taking an important exam．Some will feel dizzy or tired, some will suffer from lack of sleep, and some will lose their appetite．In fact, all these symptoms have terrible effects on our exams and we are all eager to get rid of them．
First of all, in my opinion, it’s important for us to have a right attitude towards exams．They are only a means of checking how we are getting along with our studies, so there is no need to worry too much about the results．Study hard every day and make careful plans for every exam．In this way we can avoid suffering from the pressure of exams．
Besides, enough sleep can make us energetic and enable us to perform well in an exam．Therefore, during the period of exams, we should not stay up too late．We can also try a warm bath or a cup of warm milk before going to bed．They might help us to have a sound sleep．
（We’d better go out for a walk or do some outdoor exercises before and during an exam so that we can keep ourselves relaxed and then concentrate ourselves on exams．）
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