Article in the September 29, 2008, of Washington Post said that and I quote, Joshua may be one of the most discreet White House Chief of Staff ever, seldom talking on the record to the press or appearing before outside audiences.

008年9月29日，华盛顿邮报的文章说到,我引用一下，约书亚可能是最谨慎的,白宫办公厅主任，他很少向媒体公开发表言论,很少出现在大众面前。

普林斯顿公开课 - 国际座谈会课程节选

So, for example, when people, and we'll talk about this next class, were looking at different characteristics spectra of different atoms, what they were seeing is that it appeared to be these very discreet lines that were allowed or not allowed for the different atoms to emit, but they had no way to explain this using classical physics.

举个例子，当大家看到,不同原子的特征光谱时,他们看到的是一些分离的线,那可以使不同的原子,发射或不发射出去，但是这些无法用经典物理来解释。

麻省理工公开课 - 化学原理课程节选

And when we talk about l it is a quantum number, so because it's a quantum number, we know that it can only have discreet values, it can't just be any value we want, it's very specific values.

当我们讲，l是一个量子数时，因为它是量子数，我们知道，它只能去分立的值，它不能取到所有的数，它取一些确定的数。

麻省理工公开课 - 化学原理课程节选