water white oil

例句：

1. 1.The river flows through the city,providing clean water for the people.
   这条河流流经城市，为人们提供清洁的水源。
2. 2. We need to conserve waterand reduce our usage.
   我们需要节约用水，减少使用。
3. 3. The rainwater collected from therooftop is used for irrigation.
   屋顶收集的雨水用于灌溉。