answer: Christa wants to learn the guitar from #Person2#, who is recommended by Mary. #Person2# tells Christa the time for the lesson and the cost. Christa'll come on Wednesdays.
documents: #Person1#: Hi, my name is Christa and I have a friend Mary, whose son is taking guitar lessons from you, and she suggested I call you.
  #Person2#: OK. Will the lessons be for yourself or your son?
  #Person1#: I want to learn. My son is only three.
  #Person2#: Fine. Have you had any musical experience before?
  #Person1#: Well, I studied the piano for about three months but that was 6 years ago.
  #Person2#: That's good. So we needn't start right from the beginning again.
  #Person1#: When can I take lessons and how much do they cost?
  #Person2#: Well, that depends on you. We have a small group that meets on Monday and Wednesday evenings for two hours, that costs $4 an hour. Then on Tuesdays and Thursdays I give private lessons which cost $8 an hour.
  #Person1#: I'm afraid that I can't make it on Mondays but I can come on Wednesdays.