3.In each of the following groups of words, there are four underlined letters or letter combinations marked A, B, C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation.
A、useless
B、endless
C、unless
D、hopeless
Writing: For this part, you are supposed to write an e-mail in about 100 - 120 words based on the following situation. Remember to write it clearly. 你(Li Yuan)下周一因为要去参加演讲比赛,不能上外教(Prof.Smith)的写作课。请给他写一封e-mail,内容包括:·请假并表示歉意;·解释不能上课的原因,如比赛的重要性;·承诺会自学所缺内容并按时交作业;·祝他偷快。