Dear Professor Liang,
I am writing to extend my gratitude to you. Because of your help，now I am a student of Chemistry Department of Sydney University.
Last June, when I applied to become a graduate student of Sydney University, you really gave me a lot of valuablehelp. You not only wrote a recommendation(推荐) for me to Professor Wells who works in the Sydney University，but also gave me careful and patient instructions on how to fill the application forms and write the application letters.
It is your unreserved(无保留的) help that enables me to obtain this splendid(极好的)opportunity of further education. For the following two years I will study hard to reciprocate(回报) your sincere help and expectations with excellent grades.
1. 表示歉意;2. 解释原因;3. 另约时间。
注意：1. 词数120~150;2. 可适当增加细节。
I’m very sorry that I can’t go on a trip to Beijing with you next weekend, which I have promised you. I’m writing to tell you the reason for it.
Just now, my cousin, Li Ming, who went abroad for further education last year, informed me that he would return the next Saturday morning. He asked me to pick him up at the airport with his parents. As you know, we haven’t seen each other for about a year, so I’ll have to help him in the first place.
I really hope that you can accept my apologies and understand me. I would appreciate it if you allow me to fix another time to show you around some places of interest in Beijing.
Wish you have a good time this weekend!
内容主要包括:1. 自我介绍(包括英语能力);2. 参加意图(介绍中国、了解其他国家);3. 希望获准。
注意:1. 数100左右;2. 可以适当增加细节，以使行文连贯;3. 邮件开头和结尾已为你写好.
Dear Sir or Madam,
I'm Li Hua, a middle school student from China. I read the announcement of the summer camp that you have posted on the Internet and I am interested in it.
I know that you welcome students from different countries and I'd like to take part in it. I've been learning English for 10 years, and I speak fluent English. What is more, I'll be able to tell students from other countries about China and learn about their countries as well. I hope I will be accepted as a member of your summer camp.
Looking forward to your reply!