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，硬水有高的矿物和沉积物，可以压倒表面活性剂，因此必须在洗发水中添加其他化学物来抵消使表面活性剂失效的离子作用。

As for water type, hard water that has a high mineral content can weaken the taste of tea, so it's best to use filtered water in your kettle for the optimum results.

水方面，矿物量高的硬水，会冲淡茶香；建议使用过滤水烧水，才能泡出绝佳口感。

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

但是流到我们屋子里的水, 差不多总是硬水。

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

可能会开始怀疑：我（家也）有硬水吗？

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

如果的水在通往水龙头的途中大量吸收钙和镁，就被认为是硬水。

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

硬水可以安全饮用，甚至可能对缺乏矿物的人有益。

We don't want to be boosting the yellow, as does hard water and chlorine.

我们不希望增加黄色调，硬水和氯气也是如此。

Secondly, always use filtered water, as if you use hardened water, then the flavour of the tea will react with the calcium.

其次， 务必使用过滤水，因为若使用硬水， 茶的味道会与水中的钙发生反应。