有一天，我遇到了一个以前的同学，他做副业赚了很多钱。

One day I met a former classmate of mine who was making a lot of money running a sideline.

youdao

你经常与你以前的同学通信吗？

Are you in communication with your former classmates?

youdao

她以前的同学评价她是个害羞的女孩，她在少女时期就已出落得亭亭玉立。

Described by former classmates as shy, she came out of her shell as she blossomed into a young teen.

youdao

Those of you more comfortable, rest assured we'll start filling in some gaps before long if you're already familiar with this.

那些程度比较好的同学，我们马上来讲一下以前遗漏的问题,如果你们已经熟悉这门课，那会觉得那容易接受。

哈佛公开课 - 计算机科学课程节选

This is something I used to announce near the end, but then some people felt that it's not fair not to know this from the beginning.

这些话我以前都是在期末的时候说的,但后来有些同学反映,如果不在课程一开始知道这些会很不公平

耶鲁公开课 - 基础物理课程节选

So it's really neat to think that your counterparts 100 years ago right here at MIT could have been sitting in a class where they had Lewis as their lecturer, and he's putting forth these ideas -- these are actually his lecture notes, even though it wasn't even published yet, and giving this idea of Lewis structure, which is exactly what we keep using today in order to make a lot of these predictions.

因此会有很棒的感觉，当想一想一百年以前像你们一样,在这上学的同学可能正坐在教室里,听路易斯讲课，而他正在提出这些想法-,-而这些正是他的课堂讲义，尽管当时还没有发表，但已经给出了路易斯结构的思想，这正是我们直到今天都一直在用的,用它来做很多预测。

麻省理工公开课 - 化学原理课程节选