answer: Steve invites Jan to go to London by train but Jan thinks it's expensive. Steve tells her how to get a student travel card so that she can buy cheap train tickets.
documents: #Person1#: Hi, Steve!
  #Person2#: Hi, Jan. I'm planning to go to London by train. Do you want to come with me?
  #Person1#: But it'd be cheaper by bus.
  #Person2#: I've got a student travel card. You can get cheap train tickets with it.
  #Person1#: That sounds good. How much does it cost?
  #Person2#: A card for six months is sixteen pounds.
  #Person1#: So how do I get one? You need two photographs, one for the card and one for the form.
  #Person2#: There's a photo machine in the post office. It gives you four photos for three pounds.
  #Person1#: So does the one in the library. But I went to a photographer's studio. It was cheaper.
  #Person2#: I don't have to show my passport or my driving licence, do I?
  #Person1#: No, Jan, you only need a letter from your college.
  #Person2#: OK, I'll ask my teacher for one.
  #Person1#: And then you take everything to the tourist office and ask the travel agent.
  #Person2#: Great, next time you go to London, I'm coming too!