There are many people have their favorite outdoor activities. Like basketball, cycling in the hills, volleyball and so on. My favorite outdoor activity is swimming. In summer, I often go swimming on weekends. I like it because it helps me build my body and keep healthy. And when strong water comes, I can save myself. Swimming needs skills, so I always ask my friends about the swimming skills. To be honest, I like swimming because of my friends. I can swimming with them and have a good time.