事实上，如果正确操作，所有数据绑定都保证数据不会改变。

In fact, all that data binding usually does, if operating correctly, is ensure that the data doesn't change.

youdao

这条 case 语句只是检查第二个命令行自变量，然后根据其值执行正确操作。

This case statement simply checks the second command-line argument, and performs the correct action, depending on its value. If we now type

youdao

只需要确保连接可以正确操作显卡，可以是直接连接，也可以通过一个适配器。

Just ensure the connections will work with your video card, either directly or with an adapter.

youdao

If you give me a number and a string, I'm going to concatenate them together, it's really different operations, but nonetheless, it's what it's going to do.

如果给的输入是一个数字和一个字符串，我将会把它们连接在一起，这实在是不正确的操作，但是无论如何，它就是会去这么做。

麻省理工公开课 - 计算机科学及编程导论课程节选

It's saying, if you give me two numbers, I'll do the right thing.

也就是说，如果你给我两个数字，那么操作是正确的。

麻省理工公开课 - 计算机科学及编程导论课程节选

And those are two things that you'd like to do with every looping construct you write: you'd like to be able to assure yourself that they will always terminate, and then the second thing you'd like to do, is to assure yourself that it does give you back a reasonable answer.

就是现在我有了能去检查程序,是不是做了正确的操作的能力：,这就是你们在写每个循环程序的时候,都要注意的两个事情：,第一件事情是要确保程序可以终结，第二件你要做的事情,就是要确保程序返回了正确的答案。

麻省理工公开课 - 计算机科学及编程导论课程节选