T: does it purr?
  T: does it eat people?
    T: Is it a tiger?
      N:
      N:
    T: Is it a cat?
      N:
      N:
  T: does it hiss?
    T: Is it a snake?
      N:
      N:
    T: does eat grass?
      T: Is it a sheep?
        N:
        N:
      T: Is it a dog?
        N:
        N:
T: Is it a carrot?
  N:
  N:
T: is it the hardest substance known to man?
  T: Is it a diamond?
    N:
    N:
  T: Is it a ruby?
    N:
    N: