托福阅读原文及翻译

托福阅读原文及翻译

托福阅读原文：

ElementsofLife

Thecreationofliferequiresasetofchemicalelementsformakingthe componentsofcells.LifeonEarthusesabout25ofthe92naturallyocc urringchemicalelements,althoughjust4oftheseelements—oxygen,carbon,hydrogen,andnitrogen—

makeupabout96percentofthemassoflivingorganisms.Thus,afirstr equirementforlifemightbethepresenceofmostoralloftheelements usedbylife.

Interestingly,thisrequirementcanprobablybemetbyalmostanywor ld.Scientistshavedeterminedthatallchemicalelementsintheuniv ersebesideshydrogenandhelium(andatraceamountoflithium)werep roducedbystars.Theseareknownasheavyelementsbecausetheyarehe avierthanhydrogenandhelium.Althoughalloftheseheavyelementsa requiterarecomparedtohydrogenandhelium,theyarefoundjustabou teverywhere.

Heavyelementsarecontinuallybeingmanufacturedbystarsandrelea sedintospacebystellardeaths,sotheiramountcomparedtohydrogen andheliumgraduallyriseswithtime.Heavyelementsmakeupabout2pe rcentofthechemicalcontent(bymass)ofoursolarsystem,theother9 8percentishydrogenandhelium.Insomeveryoldstarsystems,whichf ormedbeforemanyheavyelementswereproduced,theheavy-elementsharemaybelessthan0.1percent.Nevertheless,everystars ystemstudiedhasatleastsomeamountofalltheelementsusedbylife. Moreover,whenplanetesimals—

small,solidobjectsformedintheearlysolarsystemthatmayaccumul atetobecomeplanets—

condensewithinaformingstarsystem,theyareinevitablymadefromh eavyelementsbecausethemorecommonhydrogenandheliumremaingase ous.Thus,planetesimalseverywhereshouldcontaintheelementsnee dedforlife,whichmeansthatobjectsbuiltfromplanetesimals—planets,moons,asteroids,andcomets-alsocontaintheseelements.Thenatureofsolar-systemformationexplainswhyEarthcontainsalltheelementsneeded forlife,anditiswhyweexpecttheseelementstobepresentonotherwo rldsthroughoutoursolarsystem,galaxy,anduniverse.

Notethatthisargumentdoesnotchange,evenifweallowforlifeveryd ifferentfromlifeonEarth.LifeonEarthiscarbonbased,andmostbio logistsbelievethatlifeelsewhereislikelytobecarbonbasedaswel l.However,wecannotabsolutelyruleoutthepossibilityoflifewith anotherchemicalbasis,suchassiliconornitrogen.Thesetofelemen ts(ortheirrelativeproportions)usedbylifebasedonsomeotherele mentmightbesomewhatdifferentfromthatusedbycarbon-basedlifeonEarth.Buttheelementsarestillproductsofstarsandwo uldstillbepresentinplanetesimalseverywhere.Nomatterwhatkind soflifewearelookingfor,wearelikelytofindthenecessaryelement sonalmosteveryplanet,moon,asteroid,andcometintheuniverse.

Asomewhatstricterrequirementisthepresenceoftheseelementsinm oleculesthatcanbeusedasready-

madebuildingblocksforlife,justasearlyEarthprobablyhadanorga nicsoupofaminoacidsandothercomplexmolecules.Earth'sorganicm oleculeslikelycamefromsomecombinationofthreesources:chemica lreactionsintheatmosphere,chemicalreactionsneardeep-seaventsintheoceans,andmoleculescarriedtoEarthbyasteroidsan dcomets.Thefirsttwosourcescanoccuronlyonworldswithatmospher esoroceans,respectively.Butthethirdsourceshouldhavebroughts imilarmoleculestonearlyallworldsinoursolarsystem.

Studiesofmeteoritesandcometssuggestthatorganicmoleculesarew idespreadamongbothasteroidsandcomets.Becauseeachbodyintheso larsystemwasrepeatedlystruckbyasteroidsandcometsduringthepe riodknownastheheavybombardment(about4billionyearsago),eachb odyshouldhavereceivedatleastsomeorganicmolecules.However,th esemoleculestendtobedestroyedbysolarradiationonsurfacesunpr otectedbyatmospheres.Moreover,whilethesemoleculesmightstayi ntactbeneaththesurface(astheyevidentlydoonasteroidsandcomet s),theyprobablycannotreactwitheachotherunlesssomekindofliqu idorgasisavailabletomovethemabout.Thus,ifwelimitoursearchto worldsonwhichorganicmoleculesarelikelytobeinvolvedinchemica lreactions,wecanprobablyruleoutanyworldthatlacksbothanatmos phereandasurfaceorsubsurfaceliquidmedium,suchaswater.

托福阅读翻译：

生命的元素

生命的创造需要一套用于制造细胞成分的化学元素。“地球上的生命”使用了92种天然化学元素中的25种，尽管这些元素中只有4种：氧，碳，氢和氮——构成了大约96%的活生物体。因此，生命的第一个要求可能是生命需要用到的大部分或全部元素的存在。

有趣的是，几乎所有的世界都可以满足这个要求。科学家们已经确定，除了氢和氦(以及微量的锂)之外，宇宙中的所有化学元素也都是由恒星产生的。这些被称为重元素，因为它们比氢和氦重。尽管与氢和氦相比，所有这些重元素都很罕见，但它们几乎遍布各处。

重元素不断由恒星制造并通过恒星死亡释放到太空中，因此它们的量与氢和氦相比随着时间的推移逐渐增加。重元素占我们太阳系化学含量的百分之二(按质量计)，另外百分之九十八是氢和氦。在一些非常古老的恒星系统中，这些恒星系统在许多重元素出现之前形

成，重元素份额可能低于。尽管如此，所研究的每个恒星系统都至少有一定数量的生命使用的元素。而且，当星子——在早期的太阳系中形成的，可以积聚组成行星的小的固体物质——凝聚成一个稳定的行星系统，它们不可避免地由重元素制成，因为更常见的氢和氦气保持气态。因此，任何地方的星子都应该包含生命所需要的元素，这意味着由星子组成的——行星、卫星、小行星和彗星等构成的物体——也包含这些元素。太阳系形成的本质解释了为什么地球包含生命所需的所有元素，这就是为什么我们期望这些元素存在于整个太阳系，星系和宇宙中的其他世界。

请注意，即使我们允许生命与地球上的生命截然不同，这个论点也不会改变。地球上的生命是以碳为基础的，大多数生物学家认为其他地方的生活也可能以碳为基础。但是，我们不能完全排除使用另一种化学基础如硅或氮的生命的可能性。基于某些其他元素的生命所使用的元素(或其相对比例)可能与地球上基于碳的生命所使用的元素有所不同。但这些元素仍然是恒星的产物，并且仍然会在各处的星子中出现。无论我们在寻找什么样的生物，我们都可能在宇宙中的几乎每个行星，月球，小行星和彗星上找到必要的元素。

一个更严格的要求是分子中存在这些元素，这些元素可以作为现成的生命基石，就像早期的地球可能有氨基酸和其他复杂分子的有机汤一样。地球的有机分子可能来自三种来源的某一种组合：大气中的化学反应，海洋深海通风口附近的化学反应以及小行星和彗星携带到地球的分子。前两个来源分别只能出现在有大气或海洋的世界上。但是第三个来源应该给我们的太阳系中的几乎所有世界带来类似的分子。

对陨石和彗星的研究表明，有机分子在小行星和彗星中都很普遍。由于太阳系中的每个个体在被称为重度轰炸的时期(大约40亿年前)一再遭到小行星和彗星的袭击，所以每个个体至少应该接受一些有机分子。然而，这些分子往往被不受大气保护的表面上的太阳辐射破坏。此外，尽管这些分子可能会在表面下保持完整(因为它们明显对小行星和彗星有影响)，但除非某种液体或气体可用于移动它们，否则它们可能无法相互反应。因此思语国际教育认为，如果我们将

研究范围限制在仅有有机分子可能参与化学反应的世界上，我们可以排除任何缺乏大气和表面或地下液体介质(如水)的世界。

2001年1月老托福阅读解析第二篇

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1. 旅游业不但给政府带来税收而且给很多人提供了就业机会。 2. 赌博不但对健康有害，而且会影响家庭和睦。 3. 打工不但能让学生赚零花钱，而且还能让他们学到人际交往的能力。 4. 现在很多学校的校服不但贵，而且还难看，质量不好。 5. 政府不但要多建一些公路，还要鼓励人们多使用公交车。 6. 老人们既不需要很多的钱，也不需要很大的房子，他们最需要的是子女的关心和照顾。 7. 我喜欢旅游，但是，我既没有钱，也没有时间。 8. 在老人院，老人既能够接受到医疗，又能够找到很多有共同话题，共同兴趣的的伙伴。 9. 缴税既是有有利于国家，也是有利于个人。因为政府的税收主要用于公共服务，这个是每个人都会受益的。 10. 打电脑游戏既浪费时间，又有害视力。

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20. 我们应该不遗余力地保护我们的环境。 21. 现在，人们普遍认为 22. 我同意后者，有如下理由： 23. 这一观点正受到越来越多人的质疑。 24. 使用自行车有助于人们的身体健康，并极大地缓解了交通阻塞。 25. 尽管自行车有许多明显的优点，但是它也存在它的问题。 26. 在速度和舒适度方面，自行车是无法和汽车、火车这样的交通工具相比的。 27. 通过以上讨论，我们可以得出结论：自行车的优点远大于缺点，并且在现代社会它仍将发挥重要作用。 28. 这个问题已经引起了广泛关注。 29. 很多人生活在这样的幻想之中。。。

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新托福TPO19阅读原文(一)：The Roman Army's Impact on Britain TPO19-1：The Roman Army's Impact on Britain In the wake of the Roman Empire's conquest of Britain in the first century A.D., a large number of troops stayed in the new province, and these troops had a considerable impact on Britain with their camps, fortifications, and participation in the local economy. Assessing the impact of the army on the civilian population starts from the realization that the soldiers were always unevenly distributed across the country. Areas rapidly incorporated into the empire were not long affected by the military. Where the army remained stationed, its presence was much more influential. The imposition of a military base involved the requisition of native lands for both the fort and the territory needed to feed and exercise the soldiers' animals. The imposition of military rule also robbed local leaders of opportunities to participate in local government, so social development was stunted and the seeds of disaffection sown. This then meant that the military had to remain to suppress rebellion and organize government. Economic exchange was clearly very important as the Roman army brought with it very substantial spending power. Locally a fort had two kinds of impact. Its large population needed food and other supplies. Some of these were certainly brought from long distances, but demands were inevitably placed on the local area. Although goods could be requisitioned, they were usually paid for, and this probably stimulated changes in the local economy. When not campaigning, soldiers needed to be occupied; otherwise they represented a potentially dangerous source of friction and disloyalty. Hence a writing tablet dated 25 April tells of 343 men at one fort engaged on tasks like shoemaking, building a bathhouse, operating kilns, digging clay, and working lead. Such activities had a major effect on the local area, in particular with the construction of infrastructure such as roads, which improved access to remote areas. Each soldier received his pay, but in regions without a developed economy there was initially little on which it could be spent. The pool of excess cash rapidly stimulated a thriving economy outside fort gates. Some of the demand for the services

老托福2000年5月阅读解析第五篇

2000年5月第五篇 Questions 41-50 According to sociologists, there are several different ways in which a person may become recognized as the leader of a social group in the United States. In the family, traditional cultural patterns confer leadership on one or both of the parents. In other cases, Line such as friendship groups, one or more persons may gradually emerge as leaders, although support to individual members. Instrumental leaders are likely to have a rather secondary relationship to other group members. They give orders and may discipline group members who inhibit attainment of the group’s goals. Expressive leaders cultivate a more personal or primary relationship to (25) suggest, expressive leaders generally receive more personal affection from group members; instrumental leaders, if they are successful in promoting group goals, may enjoy a mote (30) distant respect.

托福TPO52 三篇阅读翻译!!倒序!!

3.Early Food Production in Sub-Saharan Africa 在更新世末期（大约公元前10000年），食品生产的技术可能已经在非洲西部和中部 的热带雨林的边缘地区使用，在那里非洲山药等根茎型植物的普遍使用，使人们认识到自己种植食物的好处。这种原始形式的“蔬菜栽培”（块根植物和树本作物的种植）可 能已经成为了一种经济传统，基于这种传统，夏季降水谷类作物的种植也采用嫁接的办法，这种种植技术已经在撒哈拉沙漠南部边界地区的草原南部被使用。随着撒哈拉 沙漠在公元前5000年之后干涸，游牧民族（牧民）向南沿着主要河道迁移到了西非和苏丹的热带草原地带。 直到公元前3000年，正如埃及文明发源于尼罗河流域一样，这些游牧民族定居在了离南部很远的东非高原地区的中心。东非高原是理想的养牛场所，如今也是像马赛人（肯尼亚和坦桑尼亚的游牧狩猎民族）这样的有名的牧牛民族的家园。直到大约公元前3300 年，第一批牧牛人出现时，高地上居住着狩猎采集者，他们居住在平原附近的山区。和其他地方的情况一样，在非洲，牛是饲养起来很费劲的动物。如果要饲养各种规模 的牛群的话，这些牛至少每24小时就需要喝一次水，而且需要大片的牧场。饲养的秘 诀在于仔细挑选放牧场地，尤其是在季节性降雨会导致全年牧草质量有明显差异的环境中。即使是规模适中的牛群也需要大片的土地和相当大的可移动性。为了获得这样的土地，经常需要牛群移动相当远的距离，甚至是从夏季牧场移动到冬季牧场。同时，放牧人不得不让牲畜在有舌蝇出没的地带吃草。唯一能够保护人类和牲畜，不患上昏 睡病（一种由舌蝇传播的疾病）的办法，就是避免在这些地区定居或者放牧——对非 洲东部和中部地区的牧民来说，这个办法严重地限制了他们的迁移。结果是，小牛群迅速地向南部地区迁移，在那里人们可以放牧。在谷类农业占领最南部的撒哈拉沙漠之前，非洲东部和南部稀树草原地区的一些依靠狩猎和采集生活的人可能已经饲养了牛群和其他家养动物，他们将牲畜作为礼物交换，或者通过劫掠放牧的邻居，来获得这些牲畜。 和主流观点相反：没有所谓的“纯粹”的牧民，即只依靠牧群生存的社会。撒哈拉沙漠地 区为了躲避干旱而向南迁移的牧民，几乎肯定的是他们也在种植高粱、小米和其他热带降雨作物。到公元前1500年，谷类作物已经广泛分布于整个撒哈拉沙漠南部的稀树 草原带。小型农业社区遍布在草原和西非东部森林的边界处，这些小型农业社区都依赖于所谓的轮耕法。这种形式的农业包括清理林地，焚烧清理过的地块上的那些被砍倒的灌木丛，将灰烬混合在土壤中，然后在这些制备好的土地上耕种。几年后，土地耗尽了养分，于是农民们继续前进，开辟新的林地，让原来的荒地休耕。轮耕法，也 被称为“刀耕火种”，高度适用于没有犁的稀树草原地区的农民，因为这种方法能够消耗 最少的能量。

新托福TPO11阅读原文及译文(一)

新托福TPO11阅读原文(一):Ancient Egyptian Sculpture TPO11-1：Ancient Egyptian Sculpture In order to understand ancient Egyptian art, it is vital to know as much as possible of the elite Egyptians' view of the world and the functions and contexts of the art produced for them. Without this knowledge we can appreciate only the formal content of Egyptian art, and we will fail to understand why it was produced or the concepts that shaped it and caused it to adopt its distinctive forms. In fact, a lack of understanding concerning the purposes of Egyptian art has often led it to be compared unfavorably with the art of other cultures: Why did the Egyptians not develop sculpture in which the body turned and twisted through space like classical Greek statuary? Why do the artists seem to get left and right confused? And why did they not discover the geometric perspective as European artists did in the Renaissance? The answer to such questions has nothing to do with a lack of skill or imagination on the part of Egyptian artists and everything to do with the purposes for which they were producing their art. The majority of three-dimensional representations, whether standing, seated, or kneeling, exhibit what is called frontality: they face straight ahead, neither twisting nor turning. When such statues are viewed in isolation, out of their original context and without knowledge of their function, it is easy to criticize them for their rigid attitudes that remained unchanged for three thousand years. Frontality is, however, directly related to the functions of Egyptian statuary and the contexts in which the statues were set up. Statues were created not for their decorative effect but to play a primary role in the cults of the gods, the king, and the dead. They were designed to be put in places where these beings could manifest themselves in order to be the recipients of ritual actions. Thus it made sense to show the statue looking ahead at what was happening in front of it, so that the living performer of the ritual could interact with the divine or deceased recipient. Very often such statues were enclosed in rectangular shrines or wall niches whose only opening was at the front, making it