permanent hard water

例句：

1. 1. The mineraldeposits in this area are responsible for the permanent hard water in the region.
   该地区的矿藏导致了该地区的永久硬水。
2. 2.The hard water can cause skin problems and damage pipes.
   硬水会导致皮肤问题和管道损坏。
3. 3. To reduce the amount of hard water in the drinking water, we need to use a water softener.
   为了减少饮用水中的硬水含量，我们需要使用软化器。