字幕列表 影片播放 列印英文字幕 Our topic for today is Water Cycle. The Sun heats up the water from oceans, lakes and rivers and water changes into water vapor by the process of evaporation. Plants also lose water in the form of water vapor from their leaves into the air by the process of transpiration. As the water vapor rises up into the air, it starts cooling down and forms tiny water droplets. These water droplets come together to form clouds. This process is called condensation. When the clouds start getting heavy and cannot hold the water droplets anymore, they fall back to the earth in the form of rain, hail or snow. This process is called precipitation. Some of the water that falls on the earth seeps into the ground. This water is available to us in the form of groundwater. The remaining water falls back into oceans, lakes, rivers and seas. This process is called collection. Then, the sun starts heating up this water once again. This circulation of water is called water cycle.