answer: Joan gets late for the first time. She tells #Person1# it's because she met a robber with a knife on the underground train, then she shares the terrible experience in detail.
documents: #Person1#: Hello, Joan. Why are you late today? You are never late for work.
  #Person2#: No, I never am, but...
  #Person1#: Wow! Your coat's very dirty! Did you fall?
  #Person2#: Yes, I had a terrible experience on the underground train. Listen to this! A man came up to me and pulled out a knife. He pointed it right at me!
  #Person1#: Oh, no! Are you all right? Did he hurt you?
  #Person2#: No, he didn't hurt me, but he took my handbag.
  #Person1#: Then what happened? What did you do?
  #Person2#: I caught hold of his knife, and he pushed me to the floor.
  #Person1#: Oh, no! Why did you catch hold of his knife? That's dangerous.
  #Person2#: I don't know. I didn't think.
  #Person1#: And what did the other passengers do? Did they help you?
  #Person2#: Yes, they did. Two men ran after the robber and held him.
  #Person1#: Did the police come?
  #Person2#: Yeah. The conductor called a policeman, and he took the robber to the police station.
  #Person1#: What a story! Thank God you're all right.