One possible version:

Dear Sam,

     I'm very glad to hear that you'll travel to China next month. Now I'll tell you something about the greatest

places of interest in our country.

     First, Beijing is the capital of China. They are so many amazing places you can't miss. For example, the

Ten-thousand-li Great Wall-one of the seven wonders in the world; the Palace Museum - the Imperial Palace

of the Qing Dynasty; Yuanmingyuan-a world famous imperial garden.

     Second, you'd better go to Xi'an of Shanxi Province for the Terracotta Warriors there. And you may also

go to Huashan- a dangerously steep mountain. It's not far from Xi'an.

     At last I hope you'll pay a visit to Hunan. Hunan is famous for Zhangjiajie-National Forest Park, a place

with beautiful mountains and rivers. By the way, have you ever heard of Mao Zedong? He was one of the

greatest leaders in Chinese history. And if you come to Shaoshan-his hometown, you'll know more about

him. 

     Oh, I must stop now. I have to get ready for my final exams.

     Good luck! 

                                                                                                                                              Yours,

                                                                                                                                              Li Liang