问答题You have promised to join your friend Mike's party, but now you can't go. Write to apologize and explain why. Marks will be awarded for content, organization, grammar and appropriateness.
【正确答案】 Dear Mike, I'm sorry, to say that I won't be able to join your party as I've promised. My brother unfortunately caught a bad cold and he has no one to take care of him. I have to go to the hospital to accompany him these days. I hope you'll have a wonderful time in your party. Yours, Andy