At the same time,they agreed to make the G20 the main group the "premier forum" to guide international economic cooperation.

VOA: special.2009.10.02

If there's a group, responsibility to help decreases and this is captured in different ways but the main idea is we all think someone else will help so we don't. There's a diffusion.

如果是一群人，帮助的责任就会分散变小,这体现在多个方面,但最主要的想法就是我们都认为别人会帮助,所以我们就不帮助了，责任被分散了。

耶鲁公开课 - 心理学导论课程节选

The leaders agreed to make the G20 the main group for their international economic cooperation, instead of the G8.

VOA: special.2009.09.26

On the other hand, the main group of people who are seeking marriages are born in the 1980s.

BBC: Q&A: Chinese dating consultant Zhou Xiaopeng

Financial advisors are the next main group of investment intermediaries, subject to even less transparency than money managers.

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The main group was the AUC - the United Self-Defence Forces of Colombia, which officially at least has demobilised.

BBC: Q&A: Colombia's civil conflict