answer: #Person1# tells #Person2# that the Blacks got divorced because Mr. Black has been two-timing. #Person2#'s surprised about that.
documents: #Person1#: The Blacks got divorced.
  #Person2#: Really? Why?
  #Person1#: Mr. Black has been getting a little on the side.
  #Person2#: Really? I am surprised. He doesn't look like a guy who'd ever cheat on his wife, does he?
  #Person1#: No, he doesn't. Anyway, his wife found out that he has been two-timing for a long time.
  #Person2#: Well, I am really surprised. By the way, have you done anything behind my back?
  #Person1#: No. The only thing I've ever done behind your back is zipping you up.
  #Person2#: I like that joke, but I hope it's true.