It allows you to define the concept of a thermometer. You have three objects, one of them could be a thermometer.

从热的物体流向冷的物体,由此我们可以定义温度，我们还可以用它来定义温度计：

麻省理工公开课 - 热力学与动力学课程节选

So I can define the efficiency of each one of them.

因此可以定义它的效率。

麻省理工公开课 - 热力学与动力学课程节选

We have one node here, and we can again define that most probable radius.

在这里有个一节点，另外我们可以定义最可能半径。

麻省理工公开课 - 化学原理课程节选

Now, in the South what developed and let's define it at least quickly what developed was one of the world's handful of true slave societies.

当时的南方变成了什么样,至少我们很快就能得出结论,当时的南方变成了世界历史上,为数不多的几个真正的奴隶社会之一

耶鲁公开课 - 美国内战与重建课程节选

If we defined food differently: that it's something that nurtures the body, something found in nature, something that doesn't harm the environment-- there are a number of criteria one can apply to define a food-- then we might come up with a different definition than this, but this is the way the nutrition field generally looks at it.

如果我们给出不同的定义,滋养身体的物质,在自然界找到的物质,不会威胁到身体的物质,有很多标准可以拿出来定义食物,我们也许可以就此重新进行定义,但这就是营养学看待食物的方式

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Once I've got that, you notice I can now define a polar point, same way. Notice I've now solved one of my problems, which is, in each one of these cases here, I'm creating both x y and radius angle values inside of there.

你们注意到我现在可以，定义一个极坐标点了，以同样的方式,请注意到现在，我已经解决了我的问题之一了，也就是，在这些例子中的每一个,我在里面都创建了x，y值。

麻省理工公开课 - 计算机科学及编程导论课程节选