At the same time, the economy itself in Mexico is going to be affected because nobody is attending classes.

VOA: standard.2009.04.30

and the first year is compulsory classes. Everybody takes the same classes.

第一年学习必修课。每个人的课程都一样。

哈佛法学院的课程 - SpeakingMax英语口语达人

I said this sentence in one of the first two classes, 'all cells are the same', and you know that's true.

我曾在头两节课的哪里讲过,所有细胞都是一样的,你们知道的

耶鲁公开课 - 生物医学工程探索课程节选

but at the same time, whenever my friends are telling about the classes they have to go,

但是，每当我朋友说起他们要上的课，

社团小组信息 - SpeakingMax英语口语达人

you always have to sit in the same room for three hours for multiple classes.

你必须在同一个房间为了多个课程坐三个小时。

对于古怪教授 - SpeakingMax英语口语达人