能的來源
【內容提示】
就下面關於幾種能的來源提示寫一篇英語文章：
①所有的能都間接或直接地來源於太陽。太陽能兩形式：一種是熱射線，一種是光射線。以月亮的光為例說明。
②電能以間接的方式來源於太陽，例如它可來自從山腰流下的水的力量。這水就是雨，而雨是由太陽的熱蒸發而來的。
③煤里的光能和熱能也是間接來自太陽。煤是由樹木和其他植物經過千百萬年前的岩石擠壓形成的，而樹木和植物是由於太陽的幫助成長起來的。
④我們用來驅動汽車引擎的能來自汽油。汽油也是由太陽的間接幫助生成的。千百萬年前死了的動植物壓在岩石下，生成石油，汽油是從石油中提煉出來的。
⑤我們可以說，幾乎所有的能都來自太陽；沒有太陽地球上就不可能有生命。
【作文示範】
Sources of Energy
Nearly all energy comes from the sun, either in a roundabout① way or straight from it, in the form of heat rays and light rays. The light from the moon, too, comes from the sun. The moon can be said to be like a large mirror which throws back the sun＇s light to the earth.
Electrical energy comes from the sun in a roundabout way, e.g.②, it can come from the power of water falling down a mountainside③. The water fell there as rain, and we know that rain is made by the sun＇s heat evaporating the water on the earth＇s surface. This water vapour rises, condenses④ on cooling, and falls as rain.
The light and heat energy from coal also comes from the sun in a roundabout way. Coal was made by the rocks pressing on trees and plants which died millions of years ago. Those trees and plants grew with the aid of sunlight, from which they made carbohydrates⑤, in this way changing the sun＇s energy into chemical energy. When we burn coal, some of this energy is set free.
Energy which we use to drive car engines comes from petrol⑥,which also was made with the aid of the sun in a roundabout way. Plants, and animals which ate the plants, died millions of years ago, and the parts of them that were left were pressed under the rocks in the 301earth. These parts left from dead animals and plants made petroleum⑦,from which petrol and oil are now obtained.
Thus we can say that the is the place where nearly all energy comes from, and that without the sun＇s heat and light, there could be no life on earth.
（選自《英語學習》1979年第8期）
【詞語解釋】
①roundabout[＇raund+?baut]a．迂迴的；不直接的
②e.g.(拉丁語) exempli gratia的縮寫，意為“例如（＝for example）”
③mountainside [＇mauntinsaid] n．山腰
④condense[k+n＇dens] v．使凝結
⑤carbohydrate[＇k%:b+u＇haidreit] n．碳水化合物
⑥petrol[＇petr+l] n．汽油
⑦ petrolem[pi＇tr+ulj+m] n．石油
【寫法指要】
本文說明各種能的成因。文章認為，幾乎世界上所有的能都以熱射線和光射線的形式直接或間接地來自太陽。作者主要分析了四種能，即電、光、熱、機械能的來源或成因。最後作者得出結論說，沒有太陽的光和熱，地球上就不會有生命。