英语书面表达：你是王琳，你的朋友Tom想请你去看电影，但是你本周要参加考试，需要复习，不能去看电影。

Dear Tom,
This is Wang Ling writing. I'm terribly sorry that I can't see the film together with you. I have to attend an important examination and I do need sufficient time to prepare for it. I will try to make up for it if possible.
Just want to say sorry to you again.

Yours
Sincerely
Wang Ling