answer: Mrs. Smith thinks that #Person1# is lying for not handing in the exercises and #Person1# claims that #Person1#'s parents are in Beijing. Mrs. Smith does not believe it.
documents: #Person1#: I'm sorry I haven't, Mrs. Smith. I've already finished the exercises, but I can't find my exercise book anywhere now.
  #Person2#: Really? I don't understand why you are always forgetting to hand in your exercise book. You are lying.
  #Person1#: Mrs. Smith, I'm not lying this time.
  #Person2#: I'm really angry with you. If you don't tell me the truth, I'll have to call your parents after class.
  #Person1#: I'm sorry my parents have gone to Beijing. They'll be back in half a month.
  #Person2#: I don't believe you. It was yesterday that I saw your parents in the supermarket. You're very clever, but you never spend your time doing your math exercises. Sit down, please. Let's get down to business.