Laughter research has found that only a small percentage of laughter, less than 20%, is a sincere response to someone's humor.
对笑容的研究表明只有小部分—不超过20%的笑容是发自肺腑的对于某人幽默的回应)f@N;6*|VA7。
In fact, laughter is primarily a social signal, as opposed to an emotional outburst.
事实上，笑容主要是一种社交讯号，而非感情释放Bn=N-7Qaln!UeqQg。

People are 30 times more likely to laugh in a social situation than when they are alone, and other observation is about laughter also imply it has a social function.
人们在人群中笑的次数是他们在独处时的30倍甚至更多，使研究人员由此推断笑容首先具有一种社交作用0W2|W=!g;N。
For instance, there's “polite” laughter. How often have you found yourself laughing at someone's attempt at being funny in order to spare their feelings or make them feel good?
例如，“礼节性”的笑容%2qmrn+qq^XR3。你发现你有多少次对别人试图表现的幽默报之一笑，只是为了照顾他们的情绪或者让他们感觉更好?

译文来自可可英语