answer: #Person2# wants to buy a diamond ring with 2 carats. #Person1# helps #Person2# choose one.
documents: #Person1#: What can I do for you?
  #Person2#: I wish to buy a diamond ring.
  #Person1#: How many carats diamond do you want?
  #Person2#: Two carats.
  #Person1#: Is this one suit for you?
  #Person2#: No, it seems too old-fashioned.
  #Person1#: What about this?
  #Person2#: Let me try it on, it's too small for me, haven't you got any larger ones?
  #Person1#: Yes, try this one please.
  #Person2#: This fits me well, how much is it?
  #Person1#: 3, 500 yuan.
  #Person2#: It's reasonable. Here you are.