假定你是李华，作为交换生，在伦敦学习时，得到了当地学校老师Mr. Nathan的悉心照顾，回国后请你给他写一封邮件表达谢意。内容包括：

1. 回忆在学校一起度过的美好时光；

2. 遇到的困难和得到的帮助。

注意：

1. 词数100左右；

2. 可适当增加细节，以使行文连贯。

参考范文：

Dear Mr. Nathan,

How is everything going? I’m writing to express my sincere gratitude to you for your care and support while I was studying in London.

I still remember vividly how you helped me adjust to life at school, always making sure I felt comfortable and included. Besides, it was kind of you to assist me with my studies whenever I struggled and to help me when I got sick. Without your guidance and kindness, I couldn’t have adapted so quickly and made the most of my exchange experience.

Thank you again for what you have done for me. Wish you all the best.

Yours,

Li Hua

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