So now, let's get a sodium here, and the chloride ion next to it to the point where they are touching.

所以，我们要有一个钠离子，和氯离子放在,相互接触的一个点上。

麻省理工公开课 - 固态化学导论课程节选

I don't know if you know how a spark plug works, but for the electrical current to fly into operation in a spark plug, the two points of contact have to be gapped.

我不知道你们是否知道,火花塞是怎样工作的，在电流通入火花塞中使它运转之前，两个接触点之间需要有空隙。

耶鲁公开课 - 文学理论导论课程节选