And so you are really good friends with like all the people you're in class with, because you know them since like four years and you have all classes together with them."

VOA: special.2009.11.05

where I would have, I think four classes one after the other on Wednesdays.

在那一段时间，我在周三会连续上四节课。

耶鲁的忙碌生活 - SpeakingMax英语口语达人

What have we done over the last three or four lectures? We've started introducing you to classes of algorithms. Things that I'd like you to be able to see are how to do some simple complexity analysis.

我们在过去三节或四节课中讲了什么？,我开始向你们,介绍算法的类型,我想你们知道的是,如何做一些简单的复杂度分析。

麻省理工公开课 - 计算机科学及编程导论课程节选

When you only have one classroom, but you have four different classes, you can only separate them by benches.

VOA: standard.2010.02.25

I remember walking around the square during mu lunch hour, walking faster and faster trying to get around, four or five different classes of kids, all of whom were verbally abusive to me, and feeling there was no place that I belong there was no place that I felt connected to other kids.

我记得我在广场周围走着,那会儿正是午餐时间，我越走越快,想翘过接下来的四五个不同的班级,班上的孩子都对我恶言相向过，我觉得自己无处可去,我找不到自己和其他孩子相联系的地方。

麻省理工公开课 - 媒体、教育、市场课程节选