問題詳情：
假設你是新華中學高一年級的李華，你的英國網友Tom來信邀請你暑假到倫敦觀光旅遊，但你因故不能赴約。請根據以下要點用英語給他寫一封電子郵件。
1.表示歉意；
2.解釋原因；
3.另約時間。
注意：1.詞數100左右；
2.不要逐條翻譯，可適當增加細節，以使行文連貫；
3.信的開頭和結尾已給出，但不計入總詞。
Dear Tom,
Thank you for inviting me to go to sightseeing in London during summer holidays.
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Best wishes!
Yours sincerely,
Li Hua
【回答】
Dear Tom,
Thank you for inviting me to go sightseeing in London during summer holidays.
It is much to my regret that I can not join you,because I will be fully occupied in preparing for New Terms' studies-Senior Two.I must do a lot of homework ,review different subjects and join in different after-class activities. What's more,my grandma is ill,so I must take care of her.I feel terribly sorry for missing the it possible for you and me to have a private meeting next time? If so,please don't hesitate to drop me a line about your preferable date.I do long for a happy journey with you.
Best wishes!
Yours sincerely,
Li Hua
知識點：提綱作文
題型：書面表達
