answer: Diana tells Peter she cannot go to Hong Kong this weekend because she has to study for an important test. Peter'll go with Dan instead.
documents: #Person1#: Hey, Peter, I'm sorry!
  #Person2#: Hi, Diana, what's wrong?
  #Person1#: We were going to Hong Kong this weekend, but I'm afraid I can't go.
  #Person2#: How come?
  #Person1#: I have a really big geography test and I have to study for it.
  #Person2#: We can go next week instead.
  #Person1#: No, I don't want to ruin your weekend. You go ahead and please take the book I bought to my friend Sally. Tell her I have to study all weekend, because I can't afford to fail the test.
  #Person2#: Ok, then I'll go with Dan. But it's a pity you can't come.