guard rows

例句：

1. 1.The police officers stood guard at the entrance of the stadium.
   警察站在体育场入口进行警戒。
2. 2.The soldiers formed a protective barrier around the wounded soldier.
   士兵们在伤员周围形成了一道防护屏障。
3. 3.The farmers marked their boundaries with stakes and flags.
   农民用桩和旗帜标记他们的界限。