假如你是李華，國際學校的教師Tom邀請你星期六參加該校舉行的"中國文化日"活動。但你爺爺突然生病住院，你要和父母一起去醫院探望，不得不謝絕他的邀請。請根據下列要點用英語給Tom寫一封電子郵件。寫作要點如下：
1.謝絕邀請；
2.說明理由；
3.預祝活動成功。
注意：
1.詞數100左右；
2.可以適當增加細節，以使行文連貫；
3.郵件開頭和結尾已為你寫好。

Dear Tom，
__________
Yours，
Li Hua

【考點】提綱作文．

【答案】Dear Tom，
Thank you very much for inviting me to attend the "Chinese Culture Day" to be held at your school this Saturday.I have been looking forward to it.I believe it will give your students more ideas about Chinese culture and will be great fun.However，much to my regret，I shall not be able to make it now.My grandpa suddenly fell ill and is in hospital.I will visit him with my parents this Saturday.
I'm awfully sorry for the sudden change of my plan and feel it a great pity to miss the opportunity to be with your students.I wish the activity a great success and hope I will have another chance to join you in the future.
Yours，
                                                                                             Li Hua