求翻译：实践就想有用，如果你要学游泳，用你学到的知识分解动作，那不是很容易吗？就算会了也是徒劳，因为你没有实践过，就算下水了也是只能喊救命。是什么意思？

Practice wanted to be useful, if you want to learn how to swim, you have learned the knowledge of decomposition action, it is not very easy to do? Even if it will be futile, because you do not practice, even if the water is also only cries for help.

I want to practice useful, if you want to learn to swim, use your knowledge breakdown, it was not so easy? Even if it is a vain, because you have no practice, even if the water is only calling for help.

The practice wants to be useful, if you must study the swimming, learns the knowledge decomposition movement with you, that is not very easy? Even if has met also is the futile effort, because you have not practiced, even if launched also is only can shout saves a life.

Practice is useful, if you want to swim, you learn of the segment, it is not very easy to do? Even if the is futile, because you have no practice, even if the water was only shouting for help.

正在翻译，请等待...