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Everyone knows that exercise is important. We all need to exercise. Doctors say i   is good for us. It makes your heart and body s   . Children who often exercise are more alert(灵活的).This means they do better in tests and schoolwork than those who don't exercise.
There are many w   to exercise. You can walk, run, swim, skate, or play ball games. Make sure you e    in the following ways: you have to like what you're doing. Exercise enough—but not too m   . It's best to exercise t    each week. Thirty minutes each time is enough. Try all kinds of things until you find one, two or even three sports that feel r    for you.
You can exercise at fitness centers(健身中心). They have 1    of equipment(设备) there. The equipment will help exercise your arms, legs and other parts of your body to make you f  . Some people buy equipment for their homes. But it is very expensive.
Exercising can be fun. Friends can exercise t     at a fitness center, or they can play sports together. How do you exercise?