it becomes a gray area but it should be pretty clear if you can treat something is reversible are irreversible.

这是个灰色区域,但什么可以当作可逆过程处理,而什么要当作不可逆过程,这是相当清楚的。

麻省理工公开课 - 热力学与动力学课程节选

And you lay out some clear guidelines on how much each person should be giving of their income.

您也给出了明确的准则，来确定,每个人该捐赠出多少的收入。

普林斯顿公开课 - 人性课程节选