guard stanchion

例句：

1. 1. The soldiers were ordered to guard the borders against intruders.
   士兵们被命令守卫边境，防止入侵者。
2. 2. The policeman was tasked with guarding the prison gates at night.
   警察被指派在夜间守卫监狱大门。
3. 3. The guards were vigilant and kept an eye on the suspicious activities around the area.
   守卫们警惕并监视着周围可疑的活动。