them active，says Shelley D.Minteer of St Louis University1.Whereas biological cells continually produce fresh enzymes，there’s no mechanism in fuel cells to replace enzymes as they quickly degrade.
Minteer and Tamara Klotzbach，also of St Louis University，have now developed polymers that wrap around an enzyme and preserve it in a microscopic pocket.“We tailor these pockets to provide the ideal microenvironment” for the enzyme，Minteer says.The polymers keep the enzyme active for months instead of days.
In the new fuel Cell，tiny polymer bags of enzyme are embedded in a membrane that coats one of the electrodes.When glucose from a sugary liquid gets into a pocket，the enzyme oxidizes it，releasing electrons and protons.The electrons cross the
membrane and enter a wire through which they travel to the other electrode，where they react with.oxygen in the atmosphere to produce water.The flow of electrons through the wire constitutes an electrical current that can generate power.
So far，the new fuel cells don’t produce much power，but the fact that they work at all is exciting，says Paul Kenis，a chemical engineer at the University of Illinois2 at Urhana-Champaign3.“Just getting it to work.” Kenis says，“is a major accomplishment.” Sugar-eating fuel cells could be an efficient way to make electricity.Sugar is easy to find. And the new fuel cells that run on it are biodegradable，so the technology wouldn’t hurt the environment.The scientists are now trying to use different enzymes that will get more power from sugar.They predict that popular products may be using the new technology in as little as 3 years.
词汇： enzyme/5enzaIm/n.酶 electrode/I5lektrEJd/n.电极platinum/5plAtinEm/n.铂，白金 membrane/5membrein/n.膜，薄膜electron/I5lektrRn/n.电子 oxidize/5Cksi7daiz/v.氧化degrade/di5reid/v.降解 glucose/5lu:kEus/n.葡萄糖polymer/5pClimE/n.聚合物 biodegradable/7baiEudi5reidEbl/adj.能进行生物降解的microenvironment n.微环境 embed/im5bed/v.埋置，插入 proton/5prEutCn/n.质子
1. According to the first paragraph，when can we share our sweet drinks with our cell phones?
A When enzymes can be commonly found in living ceils.
B When the technology of producing a new type of fuel cell appears.
C When the technology of a new type of fuel cell is suitable for mass production. D When the technology of mass producing cell phones appears. 2. What trouble did Minteer and Klotzhach have in their research? A They had trouble keeping enzymes in fuel cells active. B They had trouble keeping biological cells active. C They had trouble producing fresh enzymes.
D They had trouble finding mechanism for producing enzymes. 3. According to Paragraph 5，electrons are released
A when bags of enzyme are embedded in the new fuel cell. B when glucose from a sugary liquid goes through the enzyme.
C when the enzyme oxidizes the glucose from a sugary liquid that goes through a pocket.
D when the enzyme oxidizes the sugary liquid that goes through a pocket. 4. What is exciting about the new fuel cells?
A Their limitless power generation capacity is amazing.
B Their limited power generation capacity is a good beginning.
C Their limited power generation capacity is the result of great efforts. D Their limitless power generation capacity is a major accomplishment, 5. According to the last paragraph，what is NOT true of the new fuel cells?
A The new fuel cells run on sugar that is easy to find. B The new fuel cells are environment friendly. C The new fuel cells are biologically degradable,
D It will take some time before the new fuel cells can be used in popular products. 1. C A和D明显不是正确答案。B不是正确选择，因为只有当这种新的燃料电池被大规模生产时，才有可能实现用甜饮料给手机提供电能。 2. A 文章第三段的第一句是问题的答案。
3. C 该段第二句“When glucose from a sugary liquid penetrates a pocket，the enzyme oxidizes it，releasing electrons and proton”中的it指代glucose，而不是a sugary liquid，因此C是正确选择。
4. B 第六段的大意是，尽管这种新型燃料电池还不能产牛很多电能，但是，它能够产生电能的事实就已经是很大的成就了。因而激动人心。所以只有B是正确答案。
5. D 文章的最后一段指出了这种新型燃料电池的优点，即A、B、C所述内容。最后一句说，科学家预计，在不到三年的时间里这种新技术便可在大众的流行产品中使用。所以D是正确选择。译文：
一种新型燃料细胞通过利用活体细胞中很常见的酶能从糖中生产少量的电。如果这项技术能够成功应用于大批量生产，人们可以与自己的手机分享甜饮料(因为糖可以发电供给手机)。
燃料细胞中的化学反应能产生电流。这个过程通常依赖于贵金属，比如铂。在活体细胞中，酶发挥类似的作用，通过分解糖得到电子进而产生能量。
圣路易斯大学的Shelley D．Minteer说，以前研究人员在燃料细胞中使用酶时，很难维持酶的活性。生物细胞能不停地产生新鲜的酶，但燃料细胞中没有能替换很快降解的酶的机制。
Minteer与同样来自圣路易斯大学的TamaraKlotzbach现在研制了一种聚合物，它能包裹酶并将其保存在用显微镜才能看见的袋子里。Minteer解释说：“我们改造袋子使其能为酶提供理想的微环境。”这种聚合物能使酶保持几个月而不是几天的活性。
在新型燃料细胞中，装有酶的微小的聚合物袋子镶嵌在一张裹在一个电极上的薄膜里。含糖液体中的葡萄糖进入袋子时，酶将其氧化，释放出电子和质子。电子穿过薄膜进入一根导线并通过这根导线到达其他电子。导线中的电子与大气中的氧发生反应产生水。电子在导线中流动形成电流，电流能产生电能。
伊利诺斯大学Urbana-Champaign校区的化学工程师Paul Kenis指出，目前这种新型燃料细胞产生不了多少电能，但它们确实产生了电，这一事实令人激动。Kenis说：“单是使它可以产生电能，就是一项大的成果。”
消耗糖的燃料细胞有可能成为高效的发电工具。糖容易得到，而且消耗糖的新型燃料细胞可生物降解，因此这项技术不会损害环境。 目前，科学家们正试图利用别的能从糖中产生更多电的酶。
他们预计，在不到三年的时间里这种新技术便可在大众化的产品中使用。
第八篇Eiffel Is an Eyeful
Some2 300 meters up, near the Eiffel Tower's wind-whipped summit the world comes to scribble3. Japanese,Brazilians, Americans — they graffiti4 their names,loves and politics on the cold iron — transforming the most French of monuments into symbol of a world onthe move5.
With Paris laid out in miniature6 below，it seems strange that visitors would rather waste time marking their presence than admiring the view7. But the graffiti also raises a question ： Why, nearly 114 years after it was completed,and decades after it ceased to be the world, s tallest structure,is la Tour Eiffel still so popular8?
The reasons are as complex as the iron work that graces9 a structure some 90 stories high. But part of the answer is, no doubt, its agelessness. Regularly maintained, it should never rust away. Graffiti is regularly painted over,but the tower lives on.
\，says Hugues Richard10,a 31- year-old Frenchman who holds the record for cycling up to the tower's second floor 一 747 steps in 19 minutes and 4 seconds, without touching the floor with his feet. \，It inspires us11 ”， he says.
But to what12? After all,the tower doesn' t have a purpose. It ceased to be the world’ s tallest in 1930 when the Chrysler Building13 went up in New York. Yes，television and radio signals are beamed from the top,and Gustave Eiffel,a frenetic builder who died on December 27，aged 91 ,used its height for conducting research into weather, aerodynamics and radio communication.
But in essence the tower inspires simply by being there _ a blank canvas for visitors to make of it what they will14. To the technically minded15, it's an engineering triumph. For lovers, it's romantic.
\6”，says Isabelle Esnous, whose company manages Eiffel Tower.
词汇：Eiffel /'aifel/ Tower (法国巴黎的)埃菲尔铁塔eyeful /'aiful/ n.引人注目的景象 scribble /'skribl/ v.乱涂，乱画graffiti /grs'fizti：/ n?涂写,涂画
iron work 铁制品；铁工agelessness /'eid3lisnis/ n.永恒，永不过日寸 rust /rASt/ v.生锈（rust away 锈烂掉）frenetic /frs'netik/ a办极度激动的 tinker /'tiqko/ n.白铁匠，能做各种小修小补的人
aerodynamics /leorsudai'naemiks/ n?空气动力学
注释：Eiffel Is an Eyefiil:引人注目的埃菲尔铁塔。由于Eiffel和Eyeful读音相似，使用Eyeful而不是其他的词是有其修辞效果的。埃菲尔铁塔是古斯塔夫?埃菲尔（Gustave Eiffel，1832— 1923，法国工程师)为1889年的巴黎博览会设计的。该塔在塞纳河南岸，高300公尺（984 英尺）。埃菲尔铁塔的法文是第二段最后一句中的“la Tour Eiffel\。 some:意为“approximately;about，，（大约，将近）。如它 40 people attended the rally.大约有40个人参加了集会。
the world comes to scribble:世界各地的人们来此涂鸦。
graffiti:在此用作graffito的动词形式，意思是“涂鸦，在墙或其他表面上创作的画或铭刻”。 transforming the most French of monuments into symbol of a world on the move.使最有法兰西色彩的纪念碑成为动感世界的象征。the most + adj. + of + n.意为“在……中最
为…… 的” 如：Beethoven is the greatest of musicians.贝多芬是最伟大的音乐家。on the
move:在运动中。in miniature:小型的，小规模的，缩影的
would rather waste time marking their presence than admiring the view.宁愿花时间留下到此一游的痕迹,而不去观赏风景。would rather…than:宁愿……而不……： He would ratherstay at home watching DVD than going to the cinema.他宁愿待在家里看 DVD,而不愿到电影院去看电影。
在原句 Why is la Tour Eiffel still so popular?的 Why 与 la Tour Eiffel still so popular?之间插 AT nearly 114 years after it was completed, and decades after it ceased to be the world's tallest structure.
graces:在此作动词，意为“to give beauty, elegance, or charm to”（使……优美，优雅或具有魅力）oHugues Richard:法国自行车运动员，多次打破自行车运动的世界纪录，于2002年4月8日以19分钟零4秒的成绩骑自行车登上埃菲尔铁塔的第二层，第六次打破自行车运动的世界纪录。
“It’s iron lady,it inspires us. ”：“这是铁娘子，能让人产生灵感。”It指埃菲尔铁塔。
But to what?这是一个省略句,接着上段Hugues Richard的话发问，完整的句子可以是:But what does it inspire people to?
the Chrysler Building:是美国纽约帝国大厦（the Empire State Building)建成之前，世界第一高楼，共77层，设计师是William Van Alen。
a blank canvas for visitors to make of it what they will:—张空白的画布，任游客自由遐想 To the technically minded:对于那些善于从技术角度考虑问题的人来说，从技术的角度来说。
\：“这座塔将在我们所有的人离去后长久存在。”outlast：意为“ to last longer than”（比……持久）。out-：前缀，意思是“比…… 更…”。如：Women are said to outlive men.据说女人比男人长寿。 by a long way ：副词，意思是“大大地”。 练习：
1. Why does the author think the Eiffel Tower is transformed into symbol of a world on the move?
A) Tourists from all over the world come to the Eiffel Tower by car or by plane. B ) Tourists of all nationalities come to scribble on the cold iron of the tower. C) The Eiffel Tower is the tallest building in the world.
D ) The Eiffel Tower represents all the towers in the world. 2. What seems strange to the author?
A) Visitors prefer wasting time scribbling to enjoying the view. B ) Visitors spends much time watching other people scribbling.
C ) Only Japanese,Brazilians and Americans like to mark their presence. D ) Scribbling spread from country to country.
3. Which statement is NOT true of Hugues Richard? A ) He is a cyclist.B ) He is a record holder.
C ) He climbed 747 steps up the tower in 19 minutes and 4 seconds. D ) He cycled up to the tower's second floor. 4. What did the builder use the Eiffel Tower for?
A) Sending radio and television signals all over the world. B ) Conducting research in various fields. C) Giving people inspiration.
D ) Demonstrating French culture.
5. Which of the following is nearest in meaning to “（The Eiffel Tower is like)a blank canvas for visitors to make of it what they will ______？
A ) Visitors can do whatever they want on the tower. B ) Visitors can paint on the tower whatever they want. C ) Visitors can imagine freely what the tower represents.
D) Visitors can draw on a blank canvas provided by the Tower management company. 答案与题解：
1. B第一段提供了答案。见注释3、4、5。
2. A 第二段第一句中的句型 would rather do something than doing something else,也可以用 prefer doing something to doing something else的句型来表达。所以，A是正确选项。句型解释见注释7。
3. C第四段i诉我们,Hugues Richard蹬车上塔，打破世界纪录。C不是正确选项，因为他 cycling up to the tower's second floor,而不是 climbing up the tower.
4. B A不是正确选项，因为Gustave Eiffel没有也不可能使用该塔向全世界发射电视信号。第五段的最后一句提供了答案。
5. C第六段的大意是：对不同的人，埃菲尔铁塔有不同的象征意义。见注释14。 译文：引人注目的埃菲尔铁塔
世箅各地的人们都来到大约300米高，接近埃菲尔铁塔顶端的地方涂鸦。日本人、巴西人、美国人都在冰冷的铁上涂上自己的名字、喜好和政治观点，使这最具有法兰西色彩的纪念碑成为动感世界的象征。
从塔上可以看到巴黎市的远景，但奇怪的是观光者们宁愿花时间留下到此一游的痕迹，而不去观赏风景。但这些涂鸦者也引起了一个问题：为什么在建成114年后，埃菲尔铁塔仍然这么受欢迎?尽管它在几十年前减已经不是世界上最高的建筑物了。
这个问题的答案就像那构成90层的铁塔的工程一样复杂。一部分的理由是，毫无疑问，铁塔是永不过时的。周期性的维护使得它永远不会被腐蚀掉。埃菲尔铁塔定期油漆，覆盖那些涂鸦, 但是它仍将继续存在下去。
“埃菲尔是巴黎的象征，而巴黎又代表了法国。所以，埃菲尔十分具有象征性。” Hugues Richard说道。这位31岁的法国人保持着在19分零4秒的时间内骑自行车经过747级台阶登上铁塔二层的纪录。“这是铁娘子，能让人产生灵感，”他说。
但是它能使人们产生怎样的灵感呢？毕竟，铁塔并没有任何&的。1930年纽约的克莱斯勒大厦取代它成为世界上最高的建筑。但是电视和广播信号仍然从塔顶发送出来，而古斯塔夫?埃菲尔，这个狂热的建造者利用它的高度进行气象学、空气动力学和无线电通讯的研究。他在12月27 日逝世，终年91岁。
本质上来说，铁塔伫立在那儿本身就是一个灵感——它就像一张空白的画布，任游客自由遐想。对于那些善于从技术角度考虑伺题的人来说，它是一个工程上的胜利;而对于恋人们来说，它则象征着浪漫。
“这座塔将在我们所有的人离去后长久存在。”埃菲尔铁塔管理公司的伊莎贝尔说。
第九篇 An Essential Scientific Process
All life on the earth depends upon green plants. Using sunlight, the plants produce their own food. Then animals feed upon the plants. They take in the nutrients the plants have made and stored. But that’s not all. Sunlight also helps a plant produce oxygen. Some of the oxygen is used by the plant, but a plant usually produces more oxygen than it uses.