premise: A solo shot of a man riding a four wheeler in an atv event. hypothesis: The man entered a swimming event and is riding a jet ski.
contradiction: A man cannot be riding a four wheeler in an atv event and riding a jet ski in a swimming event simultaneously.|contradiction: The man can't be riding a jet ski and a four wheeler at the same time.|contradiction: The man can not be at a swimming event and an atv event at the same time.