He seemed a part of the darkness and silence of the forest, for no one had ever known him to smile or speak an unnecessary word.

VOA: special.2011.02.26

Now if you smiled to-- or make three people smile, and these three people-- each one makes three other people smile.

如果你的笑-,感染了三个人，这三个人-,每个人又引起另外三人发笑。

哈佛公开课 - 幸福课课程节选

Now, the person who is the mandated smiler, on three, please smile. One, two, three. Okay.

现在，要求微笑的一方，我数到三，微笑，一，二，三。

耶鲁公开课 - 心理学导论课程节选

And those nine people make three-- each one-- three other people smile.

那九个人-,每个人再用笑容感染三个人。

哈佛公开课 - 幸福课课程节选

He would be quite famous in his line of work. Whether Magda was his wife or not, one evening when he was wise-lined and gray at the temples he'd smile gravely, at a fashionable dinner party, and remind her of his youthful passion.

他会在他的行业中变得相当有名，不管Magda是否,成为他的妻子，等他有了智慧的皱纹，两鬓斑白了,他会有天晚上在一次上流社会的晚宴上，庄重地微微一笑,对她提起自己少年时代的钟情。

耶鲁公开课 - 1945年后的美国小说课程节选

What's interesting is about only one out of every ten people can fake a Duchenne smile.

有趣的是只有十分之一的人,可以伪装真正的微笑。

耶鲁公开课 - 心理学导论课程节选

The one on the right is a smile of greeting.

右边是打招呼的微笑。

耶鲁公开课 - 心理学导论课程节选

Which one's a better smile?

哪个笑的更好？

耶鲁公开课 - 心理学导论课程节选