His hair was the colour of sand.

他的头发呈沙褐色。

《牛津词典》

"Historically, it got its name because of its colour - because the water contains more mud and sand than other rivers. But now it's yellower because of human activities, " he said.

穆教授以受到水土问题影响最大的黄河流域为例说，“黄河在历史上因为含沙量高于其它河流而因颜色而得名，但如今人类活动让黄河变得更黄了。”

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When these rocks break down into the grains that make up the sand on our beaches, their colour is mostly determined by the presence or absence of iron.

当岩石分解成为颗粒够成沙滩时，颜色则是由铁元素氧化物的存在与否决定的。

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