To prevent this from happening, levodopa can be combined with other substances, like carbidopa.

VOA: special.2009.04.07

So you can think about how these 2 things combined are going to be electronegativity, which is a measure of how much an atom wants to pull electron density away from another atom.

因此你可以想象出,这两样性质合起来就是电负性，也就是一个度量，关于一个原子,有多希望把另一个原子的电子密度拉过来的。

麻省理工公开课 - 化学原理课程节选

And the question for the theorist is to show how this two can be combined should be combined and how with sensitivity to both You can perceive things that you don't otherwise.

理论家面临的问题,就是要展示这两者是能够相结合的,应该结合起来，结合时要考虑到二者的感受,你除此之外无法观察到事物。

麻省理工公开课 - 电影哲学课程节选

"More alarmingly,WHO estimates if the combined effect of decreased financial and political commitment were to be sustained or continued, this could result to a return of a half a million measles deaths each year by 2012, wiping out the gains made over the past 18 years."

VOA: standard.2010.05.21