sandur

例句：

1. 1. He used a sandur to protect his legs from the cold.
   他用一个沙袋来保护他的腿免受寒冷。
2. 2.The soldiers were using sandurs to defend their positions.
   士兵们正在使用沙袋来防守他们的位置。
3. 3. The sandur was filled with water and used as a makeshift boat.
   沙袋被装满水，用作临时的船。