Another possible explanation of the significance of depth is remember, our poor victim here.

方阵纵深的重要性的另一种可能解释,就是,记得刚才这位可怜的牺牲者吗

耶鲁公开课 - 古希腊历史简介课程节选

It's the pressure the external world is applying on this poor system here.

V是气体初态和,末态的体积之差。

麻省理工公开课 - 热力学与动力学课程节选