A second implicit purpose for the youngster-aged group is a baby-sitting purpose.

对青少年群体来说,第二个深层目标,充当临时保姆。

麻省理工公开课 - 媒体、教育、市场课程节选

One group of children was a control group; the second group was taught to think back to experience that make them laugh or smile.

一群小孩组成对照组;,有人教第二组小孩回想,让他们大笑或微笑的经历。

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