For instance,he says, a UN compound recently was hit by rocket fire, a World Food Program convoy came under attack and non-governmental organizations are frequent victims of armed robbery by criminals.

VOA: standard.2009.08.07

He said that the percent ionic character, and this is within a bond, not for a compound, for a covalent bond.

他提到离子百分数，是指一根键中，并非一个分子中。

麻省理工公开课 - 固态化学导论课程节选

So that's a good start for us putting together a skeletal structure for this compound here.

因此这对我们画这个化合物的,骨架结构来说是个好的开始。

麻省理工公开课 - 化学原理课程节选

And we could do this for our compound here, HF.

我们能为HF做计算。

麻省理工公开课 - 固态化学导论课程节选