project: water's cycle

The water

    Water is an inorganic substance composed from the hydrogen and oxygen. Water is very important for us; we need water to maintain our health. Also water is important for plants, plants need it to photosynthesis; they absorb water from the groundwater. In the world there are 1.36billion cubic kilometers of water, but only 9percent of fresh water, of which 97percent in the south, the north pol, so we can only use fresh water and only 0.2percent of total.

    In the world, water has a cycle. Water can evaporation to the water vapor, water vapor has rise to air and condensation to the clouds. So clouds were made from the water. Also clouds can precipitation, rain down in the mountain and land. In the mountain water runoff into the river or lake, sunlight evaporation it to water vapor. And in the land, water is infiltration to the groundwater. The plant uptake water from the groundwater, when plants photosynthesis they used sunlight, and sunlight can evaporation water from the plants.

    Water is very important in the world, people need save water, and prevent water pollution.
    key vocabulary:
sunlight阳光, It's the light comes from sun.
transpiration蒸腾, the plant after photosynthesis to make the water vapor.
evaporation蒸发, the water are become water vapor.
water vapor水蒸气, gas of water.
condensation缩合, the water vapor come together become cloud.
clouds筋斗云, the water vapor condensation to clouds.