"When you can't say for sure whether all the women in the advance provision group actually used the medication, then you're kind of looking at population level effect of a strategy, not the individual effect of a medication."

VOA: standard.2010.03.22

So, one difference between photoelectron spectroscopy and, for example, the photoelectric effect is that in this case, we're not just looking at one energy level, which is what we were looking at from the surface of a metal, now we're talking about this gaseous atom.

光电子能谱与光电效应的不同点在于，以这种情况为例，我们不只关心一个能级，就像原来在金属表面那样，现在我们研究的是气体原子，所以，我们可以从原子中。

麻省理工公开课 - 化学原理课程节选

Cause and effect below a certain level of definition is blurred.

在某种程度的定义的下的,因果关系是模糊的。

麻省理工公开课 - 固态化学导论课程节选

"I have agreed in principle to a new British force level of 9,500, which will be put into effect once these conditions are met,".

VOA: standard.2009.10.14