For the other groups, there was no way to punish people who did not cooperate on the public project.

VOA: special.2009.03.03

We also favor our group over others in every possible way. You are a member of many groups.

比起别的群体，我们更喜欢自己的群体,这包括我们所属的各种各样的群体。

耶鲁公开课 - 心理学导论课程节选

because that way a lot of different groups can use the same space.

因为这样一来很多不同的团队可以用同一个空间。

学生会馆的实习部门 - SpeakingMax英语口语达人

Zuckerberg compares to the way groups will spread to how photos spread.

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But the way the groups behave in Britain also explains the speed of change.

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The real issues are likely going to be in the way the two groups relate.

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