answer: #Person1# calls #Person2# to order a laptop. With #Person2#'s assistance, #Person1# buys a 15-inch black one.
documents: #Person1#: Hello, this is Dell China. What can I do for you?
  #Person2#: I want to order a laptop computer for my wife.
  #Person1#: Certainly. What type would you like to buy for her?
  #Person2#: AM520.
  #Person1#: What color does she want, a black one or a white one?
  #Person2#: She prefers a black one.
  #Person1#: All right. Have you decided what size to buy? There are different sizes to choose from, from 13-inch ones to 17-inch ones.
  #Person2#: Well, I want to buy a 15-inch one. How much does it cost?
  #Person1#: 5000 yuan, including the postage.