in both groups: the 250 here versus 250 here, which is significant sample size.

在这两组之间，样本规模相同的两组间。

哈佛公开课 - 幸福课课程节选

In addition to many lectures, we have the working groups pleased to do both experiments and to do problem-solving exercises.

我们不仅有讲座，还有不同的小组,他们将做实验,和解决问题的练习。

麻省理工公开课 - 媒体、教育、市场课程节选