water pack off

例句：

1. 1.We need to carry enough water packs for the hike.
   我们需要携带足够的水袋进行徒步旅行。
2. 2.The soldier carried a water pack on his back.
   士兵背着一个水袋。
3. 3.The campsite had a water pack ready for us.
   营地为我们准备好了水袋。