Little Tom came home from school with a new book in his hand. His mother asked him what was the book he brought home. He said that it was a prize.
Mother asked him what was the prize for. Tom said that he had received it at the lesson of Zoology when a teacher asked him of how many legs an ostrich had.
He answered it had three legs. Mother told him that an ostrich has only two legs. Tom told her that all the pupils had said it had four legs and his answer was the best.