premise: A man in black with a green cap talks to a woman sitting on a skateboard while he is drawing with chalk on the sidewalk. hypothesis: A tall man in a blue cap tried to talk the woman holding her skateboard under arm down off the building ledge.
contradiction: The man is wearing a green cap, not blue. The woman is sitting on a skateboard and not holding it under her arm. The woman is on the sidewalk and not the building ledge.