So we can do this for any final charge we have, if we have a molecule that has a charge of plus 2, then all of the formal charges should add up to plus 2 and so on.

对于任意净电荷的情况,我们都可以这样做，比如假设我们有一个带两个正电荷的分子，那么所有的形式电荷加起来应该等于正二，等等。

麻省理工公开课 - 化学原理课程节选

Being and void, being and void, so now I've got my plus two little projectile coming in, and plus two zooms right through.

有和无，有和无，现在带两个正电荷的发射体进来了，两个正电荷正好穿过。

麻省理工公开课 - 固态化学导论课程节选