premise: A child in orange poses in the snow riding a blue sled. hypothesis: A child is posing on a blue shed.
entailment: "Poses" is to tell what he does now. "Posing" is to emphasize what he does right now. Riding a sled is to sit on the sled, so the child is "on" the sled.  (Typo on your sentence 2: sled not shed).