In fact one of the frankly best things I ever did as an undergraduate was, perhaps fittingly, take this course pass-fail.

实际上我上本科时做的最得意的事,恰当地说，就是把这门课的成绩看成及格和不及格两种。

哈佛公开课 - 计算机科学课程节选

If the student hasn't mastered the basic concept, we will make sure that the grade scheme gives a failing grade.

如果学生没有掌握基本的概念，我们会确保,成绩将会不及格。

麻省理工公开课 - 固态化学导论课程节选