Dear Tom
I am sorry to tell you that I can't take part in your birthday evening party because I will take a trip with my parents to Yuannan Province for a week. It's my first time to go there so I don't want to lose this chance. Yuannan is my dream place where I have been looking forward for so many years. I apologize that I can't join your party, but I have bought a nice present for you. Hope you will enjoy your party.
Yours
Lucy
祝你学习进步，更上一层楼，快乐每一天！(*^__
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