A. Bus driver and passenger.

B. Taxi driver and passenger.

C. Teacher and student.

D. Fellow student.

16.

A. It's not as hard as expected.

B. It's too tough for some students.

C. It's much more difficult than people think.

D. It's believed to be the hardest optional course.

15.

W: Let's catch the bus to university today.

M: No way. It's too slow. I want to catch a cab instead.

Q: What's the probable relationship between the two speakers?

正确答案：D

解析：女士说：“今天我们乘公共汽车去大学吧。”男士回答：“不，那太慢了。我想坐出租车。”说话人应该是大学同学，故选D。由选项可知，本题是问说话人身份的场景题，

要根据听到的关键词判断答案。

16.

W: Is that optional course as hard as everybody says?

M: Exactly, even worse, believe it or not.

Q: What does the man say about the course?

正确答案：C

解析：一般疑问句题，yes类回答，yes后面是答案，even worse=more difficult。A项和D项都是拿听到的“hard”来做文章。