So they're optional, but they're very, very, very highly encouraged that you do these, because this is going to give you practice for the types of problems that are going to be on the exam.

虽然它们是选做的，但是它们非常非常，非常值得你们去做，因为这对你们来说是一次训练,是用来熟悉考试题型的。

麻省理工公开课 - 化学原理课程节选

We used iterative deletion in a relatively abstract setting, or not abstract, rather a play setting last time in which were choosing numbers.

我们在相对抽象的背景下探讨迭代剔除,其实也没那么抽象,比如上一讲,我们做的选数字的游戏

耶鲁公开课 - 博弈论课程节选

Because people say I've got to take that if I want to be pre-med.

据说想做医学预科生的人才选那门课吧

耶鲁公开课 - 金融市场课程节选

I'll say it again, Player i's strategy "s'i" is weakly dominated by her strategy "si" if she always does at least as well by choosing "si" than choosing "s'i" regardless of what everyone else does, and sometimes she does strictly better.

重申一下,参与者i的策略s'i,弱劣于策略si,当且仅当无论对手怎么做,她选择si的收益至少与选s'i的相等,有些情况下甚至是严格占优的

耶鲁公开课 - 博弈论课程节选