"We can't only listen once. We've got to listen twice because sometimes when the stories are told, you hear something and you learn something.

VOA: standard.2010.02.19

It was only when we started to study those that we actually understood how we can best help that population.

只有当我们开始研究这些,才能了解如何帮助到整体。

哈佛公开课 - 幸福课课程节选

We can't stand against them anymore and when you start running, the only thing the guys who are left up front can do is run.

我们打不过他们了,而你开始逃跑,留在前面的人唯一能做的也是逃跑

耶鲁公开课 - 古希腊历史简介课程节选

And that's our obligation to send them to war only when we have to, and only when we know they can actually achieve their mission is a key difference between what I advocate and what the neo-cons advocate.

我们有义务,在必须的时候，送他们上战场，我们必须确保,他们一旦奔赴战场就能完成使命,这是重大的不同,我和新型保守派主张的不同之处主要在此。

普林斯顿公开课 - 国际座谈会课程节选

So if we go to the ground state, what you see is we're at that lowest energy level, and we only have one possibility for an orbital, because when n equals 1, that's all we can do.

如果我们在基态上，你可以看到，我们在能量最低的态上，只有一种，可能的轨道，因为n等于1，只有这种可能。

麻省理工公开课 - 化学原理课程节选