【正确答案】 Dear Bob,
I am writing to express my apology to you.
Several days ago, I borrowed your music CD when I lived in your house. Unfortunately, after I came back from Canada, I found it in my luggage. I was in such a hurry that I forgot to return it to you. I will send it to you by post or express as soon as possible. If necessary, I will compensate for any troubles it may cause.
Once again, I feel so sorry for any inconvenience. Please accept my apology.
Sincerely yours, Li Ming

【答案解析】 范文很好地完成了题目规定的任务，内容要点完整。文章开篇说明的写信的目的即是道歉，然后讲述了要道歉的事情，并解释了错误的原因。第二段结尾提出了有效的解决办法。最后再次表示歉意，态度诚恳真挚。文章简洁明了，涵盖全面，成功地完成了题目的要求。