Don't fling your arms and legs about like that. Make the proper swimming strokes.

别这样乱划乱蹬，要采用正确的游泳姿势。

The principal swimming strokes are the crawl, backstroke, breaststroke and butterfly.

主要游泳姿式有爬泳、仰泳、蛙泳和蝶泳。

It will make them safer in the water, more confident and ready to learn formal swimming strokes.

这么做会使他们更安全的水，变得更自信并准备好去学习的正式游泳的姿势。

Swimming is both as a competitive sport and recreation. The principal swimming strokes are the crawl, backstroke, breaststroke and butterfly.

游泳既是竞赛运动又是娱乐。主要游泳姿式有爬泳、仰泳、蛙泳和蝶泳。

The annual event, held in honor of International bog Day, requires that flipper-outfitted snorkelers swim along a 360-foot (111-meter) stretch of bog without using conventional swimming strokes.

一年一度的该项赛事是为了纪念国际沼泽地日，比赛要求穿着脚蹼的潜水者不使用常规的游泳姿势游过一条360英尺(111米)的路程。