Both of them are self-contained courses, so you could take either 251 or 252, or you could take both.

两门课都自成一体,你可以在251号和252号中任选一个,或者都选也行

耶鲁公开课 - 金融市场课程节选

What I'm gonna do is draw a larger table, the same basic structure: I'm choosing Alpha and Beta on the rows, my pair is choosing Alpha and Beta on the columns, but now I'm going to put both grades in.

我要画个结构相同的大表格,用列来表示我选α还是β,用行来表示我对手选α还是β,但我要把两人成绩写在一个单元格里

耶鲁公开课 - 博弈论课程节选