Anchor: A skateboarder jumps off his skateboard in midair in hopes of landing back on it.
Entailed: The skateboarder is performing a trick.
Contradiction: The skateboarder is riding calmly.
Contradiction: a man on a bicycle pedals up a hill
Contradiction: A person sitting down.
Contradiction: Girl jumps off bike to perform tricks
Contradiction: A skateboarder sits.