nearly all energy come from the un, either in a roundabout① way or traight from it, in the form of heat ray and light ray. the light from the moon, too, come from the un. the moon can be aid to be like a large mirror which throw back the un light to the earth.
electrical energy come from the un in a roundabout way, e.g.②, it can come from the power of water falling down a mountainide③. the water fell there a rain, and we know that rain i made by the un heat evaporating the water on the earth urface. thi water vapour rie, condene④ on cooling, and fall a rain.the light and heat energy from coal alo come from the un in a roundabout way. coal wa made by the rock preing on tree and plant which died million of year ago. thoe tree and plant grew with the aid of unlight, from which they made carbohydrate⑤, in thi way changing the un energy into chemical energy. when we burn coal, ome of thi energy i et free.
energy which we ue to drive car engine come from petrol⑥,which alo wa made with the aid of the un in a roundabout way. plant, and animal which ate the plant, died million of year ago, and the part of them that were left were preed under the rock in the 301earth. thee part left from dead animal and plant made petroleum⑦,from which petrol and oil are now obtained.
thu we can ay that the i the place where nearly all energy come from, and that without the un heat and light, there could be no life on earth.[由wwW.HaoZuoWen.com整理]