As part of the "Hang it up and Keep it Up" campaign, the volunteers not only hang up the nets in the homes but also do follow-up visits to make sure they are being used correctly.

VOA: standard.2009.04.25

You can see that as you fill up your periodic table, it's very clear. But also we'll tell you a pneumonic device to keep that in mind, so you always remember and get the orbital energy straight.

在你们填周期表的时候，非常清楚但是我们也要告诉你们,一个策略去记住它，所以你们总是记得,并得到连续的轨道能量。

麻省理工公开课 - 化学原理课程节选

But there's also some differences that we need to keep in mind, and that will be the focus of a lot of the lecture today.

我们也有一个径向节点,但是这里也有一些区别，是我们需要记住的,那是今天报告的焦点。

麻省理工公开课 - 化学原理课程节选

We can also do a similar thing, and I'll keep my distance from the board, but we can instead be holding x constant, for example, putting x to be equal to zero, and then all we're doing is considering the electric field as a function of t.

我们也可以做类似的事情,把x固定为一个常数,例如令x等于零，然后,考虑电场作为时间的函数,这种情况下，我们划掉。

麻省理工公开课 - 化学原理课程节选