What happens in many poor neighborhoods is that a small group takes control of the water kiosk or communal tank and sets its own tariffs for the water it sells by container.

VOA: standard.2010.08.04

And that group did much better on the learning task than the control group, because they were put into a positive mood.

第二组,在学习任务上比对照组表现更好，因为他们被置于积极情绪。

哈佛公开课 - 幸福课课程节选

And then he had them take a comparative and control group an intelligence test and a memory test.

然后他对比他们和对照组的,智力和记忆力测试结果。

哈佛公开课 - 幸福课课程节选

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

Their memory improved significantly, so their intelligence level as taking by tests before and after compared to control group improved significantly after a single week.

他们的记忆力有明显改善，他们的智力水平,在实验前后进行测试，再与对照组相比,在仅仅一周后就有明显改进。

哈佛公开课 - 幸福课课程节选