Premise: "A skier races down the mountain."
Hypothesis: "A snowboarder races down the mountain."
Do we know that the hypothesis entailed by the premise? Now, let's be accurate as possible. Some thinking first:
Skiing requires the use of each foot strapped independently to an apparatus that glides over snow. A snowboarder requires the use of both feet strapped to one apparatus that glides over the snow. So, the answer is no.