Water over the dam is an expression about a past event.

VOA: special.2009.05.10

Is Lycidas an appropriate expression of grief over the death of Edward King, and furthermore, ? does it console others for their grief over Edward King's death?

利西达斯》是否恰当的表达出了,对爱德华·金之死的哀悼？，进一步说，它能否抚慰人们为爱德华·金之死的悲痛？

耶鲁公开课 - 弥尔顿课程节选

And we can simplify this expression as saying negative e squared over 4 pi, epsilon nought r squared. Epsilon nought is a constant, it's something you might see in physics as well.

也会遇到它,在这里，你可以就把它,理解为一个转换系数,我们需要做的。

麻省理工公开课 - 化学原理课程节选

In other words, the sacrificial cult was primarily a vehicle for worshipers' expression of a wide range of emotions: joy over the birth of a child, thankfulness for a good harvest and so on.

换句话说，献祭仪式从根本上来说,是表达崇拜者各种各样情感的一个途径：,新生儿带来的喜悦，对好收成的感谢，等等等等。

耶鲁公开课 - 旧约导论课程节选

You all know the expression, ? "Don't cry over spilt milk." Right?

你们都知道有句话叫做，“覆水难收“，对吗？

耶鲁公开课 - 死亡课程节选

It's difficult to imagine that as an expression of genuine grief over the death of a genuinely close friend would take the form of a poem so learned, so filled with remote literary allusions and obscure opinions.

这首诗是为表达对挚友逝去的真挚悲痛,却采取了这样一种如此博学，如此充满,遥远的幻境和隐晦的观点的形式,这确实是难以想象的。

耶鲁公开课 - 弥尔顿课程节选

RT/V this expression becomes Cv dT over T is equal to CvdT/T=-RdV/V minus R dV over V.

这样，or，RT，over，V，bar。，So，now，这个等式就,可以化成。

麻省理工公开课 - 热力学与动力学课程节选