premise1: At night, a kid in a white shirt rides the rails on his skateboard.
premise2: A young guy is skateboarding off a metal rail.
premise3: A young man skateboarding on a rail.
premise4: A boy is skateboarding at night.
premise: At night, a kid in a white shirt rides the rails on his skateboard. A young guy is skateboarding off a metal rail. A young man skateboarding on a rail. A boy is skateboarding at night.
hypothesis: A skateboarder jumping.