Back sights are indicated by reversing the from and to stations relative to the fore sight between the stations.
后瞄准器是通过将站与站之间相对于前瞄准器的方向颠倒来指示的。
2
It was still on those old streets in Chengdu. I followed you through smooth stoney road step by step. Looking at your backsight, I consoled myself: Father was still healthy.