" Radius" , " diameter" , full length, basically cutting it in half, equal points.

“半径” ，“直径” ，全长，基本上把它切成两半， 等分。

President Assad's forces have reported to have cut the narrowest point of the rebel held area to just 500 meters across.

据报道，总统阿萨德的军队与叛军控制地区最近距离只有500米。

That wouldn’t be as viable if the square had, say, 24 cut points, but with just 8 there are only so many reasonable options.

如果正方形有 24 个切点， 那将不那么可行，但只有 8 个切点， 合理的选择就这么多。