premise: A young man wearing a green shirt and a hat attempts a trick on a skateboard while riding it in a skate park next to a beach. hypothesis: A leprechaun is skateboarding.
contradiction: A leprechaun is not a young man even if he is wearing a green shirt and a hat.|contradiction: leprechaun is not a young man.|contradiction: One sentence says it is a leprechaun, the other sentence says it is a young man.