3
A. By letter.
B. Tomorrow.
C. I like writing letters.
D. Once a month.
4
A. Yes, it is.
B. Yes, I have.
C. I like the city.
D. It's a famous city.
5
A. Who are you?
B. Yes, why not?
C. There is no one here by that name.
D. I don't know.
6
A. Not likely.
B. I often drink tea at home.
C. No, thanks.
D. No problem.