translation.en: Now, something I've got very interested in is different kinds of laughter, and we have some neurobiological evidence about how human beings vocalize that suggests there might be two kinds of laughs that we have.
translation.zh: 我非常感兴趣的一点是， 「笑」有多少个不同的种类， 我们有一些关于人类表达的 神经生物学的证据表明 我们可能只有2种类型的笑。