求几片英语的科普文``初中可以理解的````初3```

求几片英语的科普文``初中可以理解的````初3```
求几片英语的科普文``初中可以理解的````初3```

求几片英语的科普文``初中可以理解的````初3```
小小昆虫本领大 每年要为美国贡献数百亿美元
摘要：
当你挥动苍蝇拍想要打死一只苍蝇或臭虫时,最好三思而后行.因为一项最新的研究结果显示,昆虫每年给美国经济带来的贡献竟然超过了570亿美元之多.
Think twice before you swat a fly or squash a bug:A newstudysays insects contribute more than $57 billion (euro47 billion)ayear to the U.S.economy.
当你挥动苍蝇拍想要打死一只苍蝇或臭虫时,最好三思而后行.因为一项最新的研究结果显示,昆虫每年给美国经济带来的贡献竟然超过了570亿美元之多.
昆虫虽小 贡献很大
据美联社日前报道,这项研究的负责人、美国科内尔大学的昆虫学副教授约翰·罗赛对此表示,不仅如此,而且上述数字还是一个非常保守的估计.他说：“大部分昆虫都在不知疲倦地行使着改善人们生活环境的职责,而它们所用的这些方式科学家们才刚刚开始了解.”
目前,有超过100万种已命名的昆虫种类,而且可能还有相同数量的未经确认的昆虫,这使它们成为地球上生活方式最为丰富多彩的物种.
诸多好处 一一列举
此项研究将重点放在了昆虫向人们提供的4种特殊服务以及如果这些小虫消失不见,人们在这些方面应该相应付出的花费上.1、野生动物的营养来源.研究人员对美国每年观察或捕猎野生动物花费多少,以及这些动物中有多少以昆虫作为食物来源进行了研究.研究得出的结论是,昆虫对美国经济的贡献价值为500亿美元.2、控制害虫.昆虫经常以其它昆虫为食.因此,研究人员对害虫造成的危害以及如果这些害虫的天敌消失,美国将要为此遭受的损失进行了分析研究.研究得出的结果是,昆虫对美国经济的贡献价值为45亿美元.3、授粉.研究人员还对那些由昆虫授粉的农作物（不包括那些由驯化蜜蜂授粉的农作物）的价值进行了估算.并由此得出结论,昆虫对美国经济的贡献价值为25亿美元.4、消化粪便.如果不是蜣螂（屎克螂）这种小昆虫在帮忙,那么在土地上施肥就会吸引更多的苍蝇和寄生虫,这样农民们就不得不想办法来解决这个问题.另外,屎克螂还有助于将营养物质重新输送回土壤.如果没有它们,辛勤劳作的农民们就要花费更多的钱来购买肥料.由此,研究人员得出的结论是,在这方面昆虫对美国经济的贡献价值为3.8亿美元.
报道说,此项研究的对象仅仅为野生昆虫为美国社会创造的财富,并不包括诸如蜂蜜和丝绸等由昆虫带来的商业产品的价值.这项研究的具体结果发表在最近一期的《生物科学》杂志上.
Think twice before you swat a fly or squash a bug:A newstudysays insects contribute more than $57 billion (euro47 billion)ayear to the U.S.economy.
And that is a very conservative estimate,said John Losey,aCornell University associate professor of entomology whoconductedthe study,published in the current issue of thejournalBioScience.
Most insects tirelessly perform ns that improve ourenvironmentand lives in ways that scientists are only beginningtounderstand,said Losey,who wrote the study with Mace Vaughanofthe Portland,Oregon-based Xerces Society forInvertebrateConservation.
There are more than 1 million named insect species _ andprobablyan equal number unidentified _ making them the mostabundant lifeform on the planet.
The study focused only on wild insects and did not count thevalueof commercially produced insect-derived products,such ashoney andsilk.
Lawrence Abrahamson,an entomologist at the State UniversityofNew York,agreed the $57 billion (euro47 billion) figureisconservative.
Most people think of insects and go yuck.They thinkaboutmosquitoes and flies.They dont realize just about everythinginlife is affected some way,somehow,by insects,he said.

Money
Everyone knows money.But how dou you know the historyof money?
Money has an insteresting history.People used to①use many kinds of of things as money.Shells were one of the first kind o...

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Money
Everyone knows money.But how dou you know the historyof money?
Money has an insteresting history.People used to①use many kinds of of things as money.Shells were one of the first kind of money,but they were not the only ones that were used as money.In china,knives and cloth were also used as money.
The first metal coins②were made in china.They were round with a square③holein the center.Different countries used different metals and designs④for their money.
Since it was inconvenient⑤for people to carry coins of metal,again the Chinese people thouht of ways to improve the money.We began to use paper money. Today,most of the money is made of paper.
注:
①used to 过去常常
②coin 硬币
③square 正方形的
④design 图案
⑤inconvenient 不方便的
音标自己查去
翻译:
人人都知道钱，但是你知道货币的起源吗？
过去，许多东西都充当过钱。贝壳是第一种被用作钱的东西，但它们并不是唯一的被充当作钱的东西。在中国，小刀和布都曾被当作钱使用。
硬币的使用起源于中国。那是中间有个正方形的孔，外边是圆形的硬币。不同国家的硬币制作材料与图案设计也有所不同。
硬币携带不方便，中国人又首先发明了纸币。今天大多数钱都是用纸做的。
Saving the Earth
How to protect the environment has become one of the most serious problems in the world.Rubbish can pollute the envionment and it is harmful to our health.So we should not throw rubbish away.Worse still, some factories put the dirty water into the rivers,lakes and the field,it kills many fish and it does great harm to the grops.
I think we should remember that we have only one Earth,we should try our best to protect the environment to make our world more beautiful..
多 good 谢
支 luck 谢
持 for 了
我 you 哦

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