单项选择题
A.How do you do B.Nice to meet you. C.Fancy meeting you here. D.Well, how have you been
A.Hello, Mr. Brown. Are you a doctor B.Moming, Prof. Brown. May I have a question C.Hi, Prof. John Brown. Can I ask what your specialty is D.Hello, Mr. John Brown. W-hat brings you here
A.Yes, you could. B.Speaking. C.Who are you D.Speak, please.