premise: A skateboarder getting ready to perform on a half-tube rink where there are trees in the background. hypothesis: A skateboarder stands on top of a halfpipe about to jump down.
entailment: "About to jump down," is a rephrasing of, "getting ready to perform.".|entailment: On a half-tube rink means on top of a half pipe and getting ready to perform means about to jump down.|entailment: A half-tube is a halfpipe.