P: 两学期各占两课时，可以选修，学生不多，名教授上课带讨论班：
https://humstudies.princeton.edu/overviews/hum-sequence/
https://humstudies.princeton.edu/humanities-sequence-faqs/
以前还有一个浓缩到一学期一课时在秋天的， little hum :The Classical Roots of Western Literature
Y: directed studies, 两学期选修，需要申请;
https://directedstudies.yale.edu/
哥大所有学生上造成老师成问题: Barely over 25 percent of Core Curriculum is taught by faculty
https://www.columbiaspectator.com/spectrum/2022/01/28/the-10-personalities-in-every-core-class/
