Putting the Sun to Work
Its a hot summer day, and you, your family, and friends decide to drive to the beach for a cookout.
When you get to the beach, the sand and the rocks are so hot that they hurt your bare feet. You put on sneakers in a hurry. The water is so bright and shining in the sun that you can hardly look at it. While the charcoal (木炭) fire is starting to burn in the cookout stove, every one goes for a swim. The water feels good warm at the top, but cooler down around your toes.
A little wind is blowing when you come out. The fire isnt quite ready for cooking yet, so you play tag or read.
For lunch there are hot dog, corn, salad and rolls, sodas, fruit, and coffee for the adults. By the time the coffee water boils and the corn and hot dogs are cooked, all the bathing suits are dry. So are the towels spread out on the rocks, in the sun.
Lunch is good. Just as you are finishing, it starts to rain so you pack up and run. But nobody minds the rain. It will cool things off.
At the same time you were having fun at the beach, work was being done. Energy from the sun was doing work. Energy, in one form or another, does all the work in the world.
Heat energy from the sun dried the towels. It heated the sand and the rocks, the water and the air. It even made the rain and the wind. Heat from the sun does small work and big work, all over the earth.
Light energy from the sun was working on the beach too. It supplied the daylight.
It lit the earth and made the sand bright and the water sparkling.
The sun also supplied the energy that grew the food you ate.
Plants use light energy from the sun to make food for themselves. The food is a kind of sugar. It is also a kind of energy called chemical energy. Green plants change light energy from the sun into chemical energy.
Plants use some of that energy for everyday living and growing. They store the rest in their leaves and seeds, in fruit, roots, stems, and berries.
The salad and the corn, the rolls, fruit, and coffee all came from plants. You and all animals depend on plants for food.
The charcoal you used for cooking began as a plant too. Once, that charcoal was a living tree that used sunlight to make food and then stored part of the food it made. The energy in this stored food remained, even after the tree died. You used that energy when you burned the charcoal.
12月大学英语六级阅读之词句解析一
名师指导英语六级考试阅读填空题
英语六级考试备考晨读美文——The Salinity of Ocean
六级文章阅读:让他们有一个梦想
名师点评英语六级试卷——阅读部分
英语六级考试备考晨读美文——The American Civil War
英语六级考试备考晨读美文——Sleep
英语六级考试备考晨读美文——Women in Colonial North America
英语六级考试备考晨读美文——Icebergs
英语六级考试备考晨读美文——Vision
12月大学英语六级阅读之词句解析三
下半年大学英语六级考试阅读考试训练 一
英语六级考试备考晨读美文——The Source of Energy
英语六级考试备考晨读美文——Coal-fired Power Plants
六级阅读考试四大类题型分析
12月六级考试冲刺——六级阅读经验谈
英语六级考试备考晨读美文——Folk Cultures
12月英语六级阅读:极端天气增加
12月英语六级阅读理解模拟练习题
12月英语六级深度阅读准确解题步骤
12月大学英语六级阅读之词句解析二
六级阅读考试高分指导:对错选项特征
英语六级考试备考晨读美文——Botany
六级阅读:女人在商界高处不胜寒
英语六级考试备考晨读美文——American Black Bears
下半年大学英语六级考试阅读考试训练二
名师指导 六级阅读考试快速解题技巧
英语六级考试备考晨读美文——Food and Health
英语六级考试备考晨读美文——Oil Refining
名师:六级阅读全面复习解读
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