So, you didn't know at the beginning, you knew you were enrolled in the trial, they gave you a shot, you didn't know whether you were part of the real group that got the test vaccine or the placebo group that got the control; turned out that Bonnie was part of the control group.

一开始你可能不清楚全过程,你只知道你参与了一项试验,他们给你打了一针,你不知道你是属于接种了,试验疫苗的真实试验组,还是属于被注射了安慰剂的空白对照组,结果显示,邦妮属于对照组

耶鲁公开课 - 生物医学工程探索课程节选

But other than that you wouldn't know that they're part of a social group

但除此以外你也不会知道他们其实属于一些社交团体，

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So, you have to imagine that this thing started with these guys back in their camp and the other army back in its camp, and they both have to agree that they want to have a battle, for a battle to take place, and they will have picked a place that is flat where they can do what they're doing.

所以事情是这样的,你得想象一下,一群人各属于不同阵营,他们都同意开战,为了进行战斗,他们需要挑选一块平地,以供双方的方阵摆开架势

耶鲁公开课 - 古希腊历史简介课程节选