假如你是汤姆，你的英语成绩很差，在美国笔友杰克的帮助下，你增强了自信心，英语学习也进步了。感谢信。

Dear Mike,
Thank you very much for your help.My English class was difficult,even though I wanted to give it up.But you help me come top,and you always tell me how to study English .You let me be more interested in English.I am very happy and relaxed.
I have sended photoes to you.Thank you so much again.
yours,
Tom.

可能文章有些错，你看看吧，OK就采纳我吧，谢谢了。。

Dear Jack:

Thank you for your help, my English has been improved a lot, previously, my English is very poor, I even want to give up, but Jack's help to make you make a spurt of progress, you impart a good method to learn English, so I am more interested in English, my English achievement is great, all thanks to you, I can improve my English, thank you.

yours,
Tom.

Dear Mike,
Thank you very much for your help.My English class was difficult,even though I wanted to give it up.But you help me come top,and you always tell me how to study English .You let me be more interested in English.I am very happy and relaxed.
I have sended photoes to you.Thank you so much again.
yours,
Tom.

这个很简单 但是内容太多了

按玻璃波波