Small groups of Confederate horse soldiers struck at the edges of the army.

VOA: special.2009.12.03

If you take one of those individual grains of sodium chloride, look at it carefully, you will see the edges look like this.

如果你拿起,氯化钠晶体的一粒，仔细观察，你可以看到这样的棱角。

麻省理工公开课 - 固态化学导论课程节选

Other earthquakes take place at the edges of continents.

VOA: special.2010.01.12