It's the same desire for some kind of sacrificial substitution that, I think, is fueling the poem's ending.

这和为诗歌最后的结尾火上浇油的，牺牲性的替代是毫无差别的。

耶鲁公开课 - 弥尔顿课程节选

You'd pull out your pencil and paper, you can do it as a matrix inversion if you know how to do that, or you can just simply do substitution of one equation into another to solve it.

你知道你在小学的时候是怎么做的对吧？,你拿出你的笔和纸,如果你会的话,你可以解一个方程组,或者你可以单纯地。

麻省理工公开课 - 计算机科学及编程导论课程节选

Bodies may last 20 years, 50 years, 80 years, 100 years, but people would only last an hour or, if it's every minute substitution, a minute.

肉体可能持续20年，50，80，或者100年，但人可能持续一个小时，以分钟算，或者是一分钟。

耶鲁公开课 - 死亡课程节选

This is a meditation on both the joy and the loss of literary substitution for the real or for the truth, the substitution of abstract pattern for something like comprehensible meaning.

对为了现实或是真理,和有着某些可理解含义的抽象模式，的文学替代的思考,在这里她有些被这宝石般的线索吸引住了。

耶鲁公开课 - 1945年后的美国小说课程节选

So now let me just do some grade school substitution.

接下来做一些简单的代换。

哈佛公开课 - 计算机科学课程节选