当我们开玩笑的时候，我们经常绷着脸或使用不笑的表情。

We often keep a straight face or use an unsmiling expression when we're making a joke.

youdao

他皮笑肉不笑的，真虚伪。

He's fake when he wears a plastic smile.

youdao

这就是我不笑的原因。

That is why I don't smile.

youdao

We laugh when there is incongruity between what we expect and what we actually--what actually happens unless the outcome is frightening."

当我们的期望和现实发生的事实,之间出现不一致时，我们就会笑,除非这种不一致引起恐惧”

耶鲁公开课 - 心理学导论课程节选

but it is to look at this and see the audience not laughing and not having... It is funny, you know.

但在一边看着观众不笑不动……也是件很有趣的事情。

街头表演很有趣 - SpeakingMax英语口语达人

It's also-- a lot of laughter isn't caused by incongruity so a lot of times when we laugh there's nothing incongruous in any deep sense about it.

还有…,很多笑不是因为不一致引起的,很多时候我们笑,并不是因为其中有不一致的现象。

耶鲁公开课 - 心理学导论课程节选