PS we've already gone through anti-miscegenation kinds of restrictions on marriage. -Yes.

而且，我们已经经历了“反对种族通婚法“这样的事,那是对于婚姻的一种限制，-是的。

普林斯顿公开课 - 人性课程节选

But you can look at manuscripts of the early eleventh century and see people singing Ps and Ls and Os and Ms and things like that.

但是大家可以看看,十一世纪初的手稿,可以看到那时有人在唱P,以及L,O和M之类的

耶鲁公开课 - 聆听音乐课程节选