水是一个大循环的一部分：水蒸发到空气中，最终又通过雨雪等降水方式回到地表，在进入这个循环之前，水通过河湖流过陆地，进入海洋。

• Water is part of a large cycle: it travels over land via rivers and lakes and through the oceans before evaporating into the atmosphere and eventually returning to the surface by precipitation.