premise: A man in a one piece tunic is riding a bike in front of a sandstone wall while touching his nose. hypothesis: The man is riding a bike.
entailment: " The man is riding a bike " is short  way of expressing "  A man in a one piece tunic is riding a bike ".|entailment: The man is riding a bike is part of his description while touching his nose.|entailment: A bike is for riding.