But the water which comes to our houses is almost always hard water.

但是流到我们屋子里的, 差不多总是。

Then you may begin to wonder: Do I have hard water?

那么你能会开始怀疑：我（家也）有吗？

Hard water is safe to drink and may even be beneficial to someone who is mineral-deficient.

以安全饮用，甚至能对缺乏矿物质的有。

If your water picks up calcium and magnesium in large amounts en route to your tap, it's considered hard water.

如果你的在通往龙头的途中大量吸收钙和镁，那就被认为是。

It goes through a course of hard water and Chicago dirt and comes up looking like a rose leaf with the morning dew on it.

它经过一段和芝加哥的泥土， 看起来像一片玫瑰叶， 上面有晨露。

Hard water, for example, has higher mineral and deposit content that can overwhelm a surfactant, so other chemicals have to be added to the shampoo to counteract the ions that make the surfactants ineffective.

例如，含有较高的矿物质和沉积物，以压倒表面活性剂，因此必须在洗发中添加其他化学物质来抵消使表面活性剂失效的离子作用。