answer: #Person1# wants to have an interview. Mary suggests #Person1# make an appointment before the interview because the interviewers might be busy.
documents: #Person1#: Mary, this company is pretty good. I really want to have an interview.
  #Person2#: Have you made an appointment with this company?
  #Person1#: Not yet. Do I have to?
  #Person2#: Yes, it's very important to make an appointment before the interview.
  #Person1#: Why?
  #Person2#: If you go to the company without appointment, the interviewers may happen to be busy with other things, and have no time to give you an interview.
  #Person1#: Yes, you are right.
  #Person2#: If the interviewers are not in the company, you will go there for nothing.
  #Person1#: Sure. Why didn't I think of that?
  #Person2#: So you should make an appointment in advance with the company for the interview.
  #Person1#: Then how can I make the appointment?
  #Person2#: You could directly call the company and arrange the time and place for the interview.
  #Person1#: Ok, I see.
  #Person2#: If you succeed in doing that, you must attend the interview on time.