[填空题]Sports and games make our bodies strong, prevent us from getting too fat, and keep us healthy. But these are not their only use. They give us{{U}} (36) {{/U}}practice in making eyes, brain and muscles work together. In tennis, our eyes see the ball coming,{{U}} (37) {{/U}}its speed and direction and pass this information on to the brain. The brain then has to decide what to do, and to send its orders to the{{U}} (38) {{/U}}of the arms, legs, and so on, so that the ball is met and hit back where it{{U}} (39) {{/U}}to go. All this must happen with very great{{U}} (40) {{/U}}, and only those who have had a lot of practice at tennis can carry out this complicated{{U}} (41) {{/U}}of events successfully. For those who work with their brains most of the day, the practice of such skills is especially useful. Sports and games are also very useful for{{U}} (42) {{/U}}. In their lessons at school, boys and girls may learn about such virtues as unselfishness, courage,{{U}} (43)