When monkeys get together to kill and eat somebody they make a kind of a laughing noise and chimpanzees laugh when they tickle each other.

猴子一起猎杀其他动物时,它们会发生出一种笑声,黑猩猩胳肢时也会笑。

耶鲁公开课 - 心理学导论课程节选

If you laugh, I'm going to assume you are laughing at me.

如果你们在笑,我会假设你们在笑话我

耶鲁公开课 - 基础物理课程节选