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

They smiled. I pointed my finger at them and said, " If you keep this up, you'll both go crazy but let me know what happens as you go along."

他们笑了，我指着他们说“,如果你们继续这样，你们都会疯的,但你们继续的时候得让我知道“

耶鲁公开课 - 1945年后的美国小说课程节选