QIU was a famous chess player. Nobody in the whole country could beat him on the chessboard. Two students came to learn chess from him. One of them always concentrated his attention to learn from him with all his mind. The other also sat there and listened to him, and his eyes were also on the chess pieces. But he was more interested in bird-shooting. His mind was always on the wild geese flying in the sky and on how to shoot them with bow and arrow. One student learned it very quickly, while the other did not learn as well as the first student. Why? Was one student more clever than the other? Of course not. It was only because one of them did not concentrate his attention.