auxiliary water source

例句：

1. 1. The city's main water sourceis a reservoir located in the mountains.
   该市的主要水源是一个位于山区的水库。
2. 2.The auxiliary water source wascrucial for the survival of the villagersduring the drought.
   在干旱期间，这个辅助水源对村民的生存至关重要。
3. 3. The governmenthas been working on developing an auxiliary water source to alleviate the shortageof freshwater.
   政府一直在努力开发一个辅助水源，以缓解淡水短缺的问题。