We're still close enough to the summer that the air is not just filling us up with extra static electricity, so it's a little more challenging here.

我们现在离夏天更近了,这样空气中不总是,充满额外的静电，所以这时做实验,会有一些挑战性。

麻省理工公开课 - 化学原理课程节选

So, instead of having the periodic variation of water, or the periodic variation of air density here we're talking about an electric field.

不像水或者空气密度的,周期变化，我们这里,讨论的是电场。

麻省理工公开课 - 化学原理课程节选

You have a block here and then you have something above there floating in mid air.

你在这里放一个木块,让某物漂浮在木块之上

耶鲁公开课 - 心理学导论课程节选