This year it will be observed on Monday, January 19th.

VOA: special.2009.01.16

Let's call someting invisible not only it can't be seen, not only it can't be observed, but it can't be detected at all.

让我们把一些不仅是看不见的,不仅是观察不到的，而且是完全检测不到的，东西称为无形的。

耶鲁公开课 - 死亡课程节选

Then he observed, through time, after subjecting pigeons to this torture for some time -it might be not approved by--it's not really torture, it's like dieting or something, you've all lived through that, right?

随着时间流逝,他还观察,在这酷刑实施了一段时间后,也不能真的说是酷刑,其实有点像节食之类的,你们很多人也节食过,对吧

耶鲁公开课 - 金融市场课程节选