假设你是李华,刚从英国参加交流活动回来,想给你的房东发一封邮件表示感谢.怎样写一篇英语作文

Dear XXX,
Hello.This is Li Hua.Thank you very much for your great treat when I was in the UK for an exchange activity.That's very kind of you to do so.I have just returned from the UK and