But many also say they do not have enough time to do the work themselves and are under great pressure to do well in school.

VOA: special.2009.04.23

And actually, a question that might come up, I just explained, the sodium channel, you might say, well, how do potassium channels work then, because I can understand how you can filter something big out, but how do you filter out something small.

实际上，可能大家会问一个问题，我刚解释过，钠离子通道，你可以说，好吧，那么钾离子通道该如何起作用呢，因为我可以理解你是如何把大东西过滤掉的，但是你如何把小东西过滤掉呢？

麻省理工公开课 - 化学原理课程节选

OK, so let's go through this and see what we would do which is to calculate the heat and the work. This is well insulated.

好的，让我们开始然后看看,我们该怎样计算热量和功的大小,这是完全绝热的，所以。

麻省理工公开课 - 热力学与动力学课程节选

So how do chess-playing programs, and particularly the best chess-playing programs, how do they work? Well, they play chess the same way you do.

那么,下棋程序,特别是最好的下棋程序,是如何工作的呢,它们的下棋方式同你们如出一辙

耶鲁公开课 - 死亡课程节选