answer: #Person2# helps #Person1# buy an English-Chinese dictionary. #Person1# chooses the paperback version because it is cheaper.
documents: #Person1#: Do you have a good English-Chinese dictionary?
  #Person2#: Sure. How about this one?
  #Person1#: Is this the latest edition?
  #Person2#: Yes. We have both the paperback and the hardcover.
  #Person1#: What's the difference?
  #Person2#: The hardcover is more expensive.
  #Person1#: Oh! I see. I'll have the paperback, please.