她按四人一组把全班分成若干小组。

She split the class into groups of four.

《牛津词典》

学生两人一组做这个项目。

Students worked in pairs on the project.

《牛津词典》

首先让学生分成四人一组。

First get students to form groups of four.

《牛津词典》

I just wanted to show you this last graph, or this last set of statistics to go from causes of death in the U. S.

我想让你们看的最后一张图,或者说最后一组统计数据,不是关于美国人的死因

耶鲁公开课 - 生物医学工程探索课程节选

so it's a 250-person class, but we have a group of 50 that we go around with quite a bit.

这是一门250人的课，但是我们组成50人一组一起学习。

跟校友们的关系 - SpeakingMax英语口语达人

Well, a cross-sectional study would mean that you'd get a random group of the population and measure them in 1970 and then take another random group five years later and measure them, but it wouldn't be the same people necessarily, it would be different groups of people.

那么,横断面研究就是,1970年你在人群中随意选择一组人,并记录下相关数据,然后,五年后再随意选择一组人记录数据,但这不需要是同一组人,通常是不同的人

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选