Many students are short of exercise in their spare time now. For one thing, they have too much homework to do. For another, they probably have so many after-school classes such as playing the piano. So there is no time for them to do exercise.Less exercise is harmful to students. They are growing quickly, so they need to play sports to make their bodies strong and relax after study for a long time. I think they had better exercise in their daily time. First, they can take a walk after dinner on weekdays. Second, they can go outdoors to play sports on weekends, such as playing basketball, and climbing mountains. .