a. 体育运动的好处
b. 体育运动可能带来的副作用
c. 我参加体育活动的体会

Sports do us good in many respects (TS). It goes without saying that taking exercises can build up our physical strength. In collective sports like basketball, volleyball, or football, we will learn the importance of cooperation. While taking part in sports game, we will try our best to win and arouse ourselves the competitive spirit. Sports can also help us relax after a period of exhausting work. However, as the saying goes, "there are two sides to everything", and sports is without exception. We may hurt other players or ourselves if we are not careful enough when participating in sports activities. What's more, excessive or severe training can do harm to our health.
My participation in sports tells me that sports can make us healthy both physically and psychologically. It is also a good way for people to know each other and can promote friendship between people. So long as we are carefully enough, sports can do us nothing but good.