Describe the water-cycle in nature.
Water constantly moves from the earth to the air and again comes down to the earth in the form of rain. Water from seas, rivers lakes, ponds, puddles and streams evaporates due to the heat of the sun. Plants too give out large amounts of water from their leaves. Water vapours rise up. The air higher up in the atmosphere is cooler which cools the water vapours and condenses to form tiny droplets of water on small dust particles. These droplets combine to form clouds. The clouds get cooled further, the water drops become bigger. When they become too heavy, they fall on the earth as rain. The rain- water again forms seas, rivers, lakes, ponds and streams and it again evaporates to the air, thus the water-cycle in nature continues.