answer: #Person1#'s guiding a tour in the National Forest Park and tells #Person2# about the stones and trees.
documents: #Person1#: Ladies and gentlemen, now we are in the National Forest Park.
  #Person2#: What's that?
  #Person1#: The stone is a prehistoric log. It was turned to stone millions of years ago.
  #Person2#: Really? It's unbelievable.
  #Person1#: But it's the truth.
  #Person2#: Do you have Ginkgo trees here?
  #Person1#: We don't have them here, I'm afraid. Ginkgo trees grow well only in cold weather.
  #Person2#: What are these trees opposite to the pine trees?
  #Person1#: They are poplar trees. They are widely used in our lives.
  #Person2#: I think I know that.