单项选择题
A:Oh. But why didn't he just own up and tell someone? B:（）
A. So be careful with our job B. He was too scared that he would be fired, I suppose C. You should have told him that earlier
单项选择题 A:Here you are, Sir. B:（）
单项选择题 A: Could I talk to Prof. Lee? B:（）
单项选择题 A:Hello, Im Susan. Nice to meet you. B:（）
