That happens because of space issues that you were asked to do that, because you can always assume that all of the core orbitals are already going to be filled.

这是出于空间的考虑,要求你这么做是因为，你总是可以假定所有的,芯电子轨道都已经填满了。

麻省理工公开课 - 化学原理课程节选

I think especially when you get to the UN with much of the UN's core bases, European..., the anti-death penalty, even beyond "women's issues".

尤其是牵涉到联合国的时候,联合国的那些核心基地，欧洲的，废除死刑，消除“女性问题“等等。

普林斯顿公开课 - 人性课程节选

The other threat is eonomic, and all the economic issues are tied in my judgement, to the same core problem which is the long-term fiscal challenge that this country faces.

另一个威胁是经济方面的，我认为所有的经济问题,都和一个核心的问题分不开,就是我们国家面临的,长期财政挑战。

普林斯顿公开课 - 国际座谈会课程节选