Breaststroke 蛙泳
Breaststroke is
the slowest of the four official styles in competitive swimming, but it is commonly agreed that it is by far the most difficult to do correctly. The history of breaststroke goes back to the Stone Age. The leg action of the breaststroke may have originated by imitating the swimming action of frogs.
蛙泳是竞技游泳的四种标准泳姿中最慢的一种，但它却是公认最难做得标准的一种。蛙泳的起源可以追溯到石器时代。蛙泳中腿部蹬水的动作很可能是模仿青蛙的泳姿而来
Freestyle 自由泳
Freestyle is an unregulated swimming style used in swimming competitions according to the rules of FINA. Competitors in freestyle swimming can use any of the unregulated strokes such as front crawl, dog paddle, or sidestroke, etc. Most competitive swimmers choose the front crawl during freestyle competitions, as this style provides the greatest speed. As such the term freestyle is often used as a synonym for the front crawl.
根据国际泳联的规定，“自由泳”其实是各种非标准泳姿的统称，包括爬泳、狗刨、侧泳等等。但是在自由泳比赛中多数选手会选择爬泳，因为这种泳姿速度相对较快。因此人们常说的“自由泳”基本就成了“爬泳”的同义词。
Backstroke 仰泳
The backstroke has the advantage of easy breathing, but the disadvantage of swimmers not being able to see where they are going. It is also the only competition swimming style that starts in the water. Backstroke is an ancient style of swimming. The first Olympic backstroke competition was the 1900 Paris Olympics men's 200 metre.
仰泳的优势在于便于呼吸，缺点则是游泳者不能看到前方的情况。仰泳也是几种竞技泳姿中唯一一种从水中出发的（其他几种泳姿是从跳台上出发）。仰泳是一种古老的泳姿。奥运史上第一次仰泳比赛是1900年的巴黎奥运会男子200米仰泳。
Butterfly stroke 蝶泳
While other styles like the breaststroke, front crawl, or backstroke can be swum easily even by beginners, the butterfly is a more difficult stroke that requires good technique to be feasible. It is the newest swimming style swum in competition, first swum in 1933. Interstingly, the butterfly kick was developed separately, and is also known as the "dolphin kick".
初学者也许能很容易地掌握蛙泳、自由泳或仰泳，但蝶泳却难得多，对游泳者的技术要求很高。蝶泳出现于1933年，是竞技游泳的几种泳姿中最新的一种。有趣的是，蝶泳的踢水动作是单独发展出来的，而且被叫做“海豚踢”。
