No, the classes fall into a separate category.

不，这些课程属于一个单独的类别。

youdao

The students who are most successful are usually the ones who come to all the classes.

成绩最好的学生往往是出全勤的那些。

《牛津词典》

But one of the classes I registered for is missing.

但是我报名的课少了一节。

youdao

She complains that her school does not offer the classes she and other students would like to take.

VOA: standard.2009.12.08

This was even longer than that. But also I would have to write this thing for one of the classes,

去年那段时间比高中的学习时间还长。而且我们还要写一些东西，

耶鲁的忙碌生活 - SpeakingMax英语口语达人

So, just an introduction to the classes of potential foreign invaders that our immune system tries to defend us against.

所以 我只是简单介绍几类,免疫系统试图抵御的潜在外来侵略者

耶鲁公开课 - 生物医学工程探索课程节选

However, in America, the classes are not fixed and those generating wealth expand the pie.

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Even those watching the classes are tapping their feet and swaying to the beat.

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"For the amount of money I'm paying, you'd think the classes would be smaller, " he says.

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