premise: A skinny shirtless man wearing sunglasses, a tiger scarf around his neck and a black belt and jeans is hammering on a metal rod. hypothesis: An overweight man in a business suit shoves a plastic rod into the soil.
contradiction: The man can't be skinny and overweight. He also can't be shirtless wearing a tiger scarf, black belt, and jeans while wearing a business suit. Hammering requires some other object to hit the object of interest, shoving is usually just done with the hand. The rod can't be both metal and plastic.