Mangroves are the most readily available source of firewood for fires to boil seawater and what is called "salt dust" scraped from the soil.

VOA: standard.2010.03.29

A cubic kilometer of seawater, go into the ocean and imagine a box .

一千立方米的海水，想象一下一个体积为一千立方米的盒子。

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And, seawater contains only 3.7% of the total magnesium present 7% in the Earth's crust.

而海水只含有,地表镁总量的,3。

麻省理工公开课 - 固态化学导论课程节选

By now the cabin boy, Parker, is lying at the bottom of the lifeboat in the corner because he had drunk seawater against the advice of the others and he had become ill and he appeared to be dying.

现在派克正蜷缩在救生艇的角落,因为他不顾众人劝阻饮用了海水,他生病了，而且似乎快死了。

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You get that out of 1 cubic kilometer of seawater.

你能从一千立方米海水中得到这么多。

麻省理工公开课 - 固态化学导论课程节选