地球不會干涸

Water is one of the great examples of how Earth recycles. Water on Earth's surface evaporates1， making water vapor2 The vapor cools， which makes clouds. Eventually all of it comes back to Earth as rain， snow， or some other kind of precipitation3. That gives the water that plants need to grow and the water that flows to make rivers and fill up the oceans. In our solar system， Earth is the lucky planet that has the right temperatures to recycle water.

水是地球如何進(jìn)行再循環(huán)的最好例子之一。地球表面的水蒸發(fā)形成水蒸氣。水蒸氣冷卻又形成云。最終所有水蒸氣以降雨、降雪或其他降水形式回歸地球。這樣一來又可以供給植物賴以生長的水，水又可以匯成江河，注入海洋。在太陽系中地球是個幸運(yùn)的星球，因為它有適宜的溫度可以使水再循環(huán)。

注釋：

1．evaporate vi．蒸發(fā)，揮發(fā)

2．vapor n．[美]＝vapour蒸氣，汽

3．precipitationn．[氣][物]（雨、露、雪等的）降落