交换生帮你修好了自行车,用英语怎么写感谢信给他。

Hi, my classmate XX:
Thank you for helping me fix up my bike on my way to class. I used my full strength to ride my bike that the chain was out of the axis. You spotted my panic expression and stopped to help me put the chain back to its place. Consequently, the mechanic oil has stained your hand I felt so sorry. You are so kind. I am lucky to have met such a helpful people like you. Thank you again.
Your classmate: Li Ming.