Everyone knows that exercise is important. We all need to exercise. Doctors say it is good for us. It makes your heart and body strong. Children who often exercise are more alert(机灵的). This means they do better in tests and schoolwork than those who don’t exercise. There are many ways to exercise. You can walk, run, swim, skate or play ball s. Make sure you exercise in the following ways: you have to like what you are doing, exercise enough but not too much. It’s best to exercise twice each week. Thirty minutes each time is enough. Try all kinds of things until you find one, two or even three sports that are right for you. You can exercise at fitness centers. They have a lot of equipment (设备) there. The equipment will help exercise your arms, legs, and other parts of your body to make you fit . Some people buy equipment for their homes. But it is very expensive. Exercising can be fun. Friends can exercise together at a fitness center, or they can play sports together. How do you exercise? 根据短文内容，选择正确答案。 小题1:Which of the following sports is not in the text? A．Fishing. B．Running. C．Swimming. D．Walking. 小题2:How many times should you exercise each week? A．One time. B．Two times. C．Three times. D．Four times. 小题3:The words “fitness centers” in the text mean __________. A．商务中心 B．健身中心 C．购物中心 D．医疗中心 小题4:The equipment in fitness centers will help exercise your _______. A. arms B. legs C. other parts of the body D. A、B and C