[解析]
Dear Jonathan,
I can't tell you how much I appreciated your kindness in letting me stay at your home while I was in London.【高分句型一】It was a delight to see a loving family.You kept me company and created a great home atmosphere for me.I shall always treasure the time when we were together.(感谢Jonathan一家人的照顾)
Next summer,I will graduate from senior high school and it will be about two months before I go to university,so my parents and I would really like you to come here on vacation.【高分句型二】There are a lot of beautiful and historic places in Xi'an.I'm sure you will like it.Meanwhile,we will have a nice time and enjoy ourselves again.(自己明年的计划并且Jonathan 暑期来西安度假)
I'm looking forward to your reply.Please send my best regards to your parents!(期盼回信并且问候他的家人)
Yours,
Li Ming