Water goes around and around Earth in a never ending journey called the water cycle（循环）. The sun heats up lakes, oceans, and other wet places on Earth. When the water gets warm enough, it changes into vapour. Plants also give off lots of water vapour. Some of this water vapour cools off high in the sky and becomes clouds. Then it falls back to Earth in a new place as rain or snow. This cycle happens over and over again. The ground can absorb water like a sponge (海绵). If you could see this groundwater, it wouldn’t look like a lake or river. The groundwater is mixed in with the rocks and sand that lie in layers(层) below Earth’s surface. Groundwater moves along slowly. How slowly? Maybe 1.5 kilometres in one century. Some of this water has been underground for thousands of years. And once groundwater is pumped out of the ground from a deep well（井） by people, it may take hundreds of years for another water to take its place. 小题1:In which order does water go around Earth? a .Fall down as rain or snow. b. Heated up by the sun on lakes, oceans and other wet places. c. Cool off high in the sky. d. Form clouds. e. Change into vapour.
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