Soap does not lather well in hard water.

肥皂在硬水中起不了多少泡沫。

《牛津词典》

Hard water furred the kettle.

硬水使水壶生了垢。

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"If you live in a hard water area, use cooled boiled water from the kettle," says Richards.

“如果你是生活在硬水区，要使用水壶中冷却的煮沸的水，”Richards说。

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A company that can keep its head above water can survive economic hard times.

VOA: special.2009.05.10

Cattle and buffalo wastes. Water was hard to find,too.

VOA: special.2010.04.15

grass and water sometimes hard to find.

VOA: special.2010.03.18

Softer water, says Dietrich, can have a different "ecology" to hard water.

BBC: Is there really a north-south water taste divide?

It found that most cases involved contact lens wearers in southern England and suggested hard water in the area could be to blame.

BBC: Blindness risk for contact lens wearers

Limescale in hard water allows the growth of amoebae and the infection seems to be caused when wearers allow tap water to come into contact with their lenses when storing them or washing and showering.

BBC: Blindness risk for contact lens wearers