Corals are anthozoans, the largest class of organisms in the cnidaria group.

VOA: special.2010.08.10

They don't seem to be an ethnic group so much as a marginalized social class, but some have suggested a connection with the word "Hebrew."

他们并不像是少数民族,而更像是边缘化的社会阶级，但有些人指出它与希伯来这个词有关联“

耶鲁公开课 - 旧约导论课程节选

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

But also, the students put in actually more time into the class and they outperformed the control group.

而且学生对课业,付出更多时间，成绩比对照组好。

哈佛公开课 - 幸福课课程节选

By combining elements as it were of the few and the many polity is characterized by the dominance of the middle class the middle group.

透过结合一些元素,就像前人所为，结合少数人与多数人,政体的特征便转为是,由中间阶级，中间团体所统治。

耶鲁公开课 - 政治哲学导论课程节选

What do I have to do to this class-- this side of the class to put you in a different group from this side and different from that side?

我要对这个班做什么-,才能让坐在这一边的同学,和坐在那边的同学处于不同的群体？

耶鲁公开课 - 心理学导论课程节选

They did this because they didn't want the upper-class in Rome, who were the elite, they didn't want any one household, or any small group of households, to become too powerful.

因为他们不想罗马的上层阶级，即精英阶层，一户独大。

耶鲁公开课 - 新约课程节选