1、One possible version:

Dear Sir or Madame,

   ①I’m very glad to be invited to the English summer camp

   ②I prefer to go in July because I’ll have to prepare myself for the new school term in August. ③It seems all the activities you offer are attractive and meaningful. But I’d like to attend the English lectures, from which I can get more information on British and American culture. ④With the coming of the 2008 Beijing Olympic Games, more and more foreigners are eager to know about China. So I hope to teach foreigners Chinese and spread Chinese culture.

   ⑤It’s been a dream for me to visit Beijing. Could you organize a tour around the city during the camp?   

Thank you very much.

                                                     Yours truly,

                                                      Li Dong