话题一：建议信
　　预测题目：
　　direction: you have received a letter from your friend who is admitted to peking university and wants you to provide some suggestion to him about which subject to specialize in. write him a letter to
　　1) tell him your suggestion, and
　　2) explain your reasons.
　　you should write about 100 words on answer sheet 2.
　　do not sign your own name at the end of the letter. use zhang wei instead.
　　do not write the address. (10 points)
　　核心词汇：