can be easily made to demonstrate英语作文

A “solar still” can be easily made to demonstrate that there is often water in even the driest places. we can collect water with little more than a sheet of plastic and a container.

We first dig a hole several feet deep in the ground and place a container at its center. put as much green living plant material as you can find around the container. grass, tree leaves and other plants all contain water. in the day time the sun causes water in the plants to evaporate.

Place the plastic film over the hole using stones to keep it in place as the diagram shows. leaving a dip in the center, the plants’ water will condense on the inside of the plastic and will drip into the container. we can also collect early morning dew in the center of the dip too.

Evaporation is the name of the process when water turns from a liquid into a gas. condensation is the process when water turns from a gas to a liquid.