It's simply a convention established after the fact that allows us to organize material in ways that we can grapple with it ways that we can understand it.

这仅仅是在事后建立的一种惯例,好让我们组织材料,用容易整理的方式,用容易理解的方式

耶鲁公开课 - 聆听音乐课程节选

Because in Germany everything is like, sorted out for you and very professional.

因为在德国，一切都给你整理好了，很专业。

一见钟情的学校 - SpeakingMax英语口语达人