【文章內(nèi)容簡介】 enjoy listening to your favorite music on CDs 語法上可以理解為 there is no doubt （about the fact that） you will continue to enjoy listening to your favorite music on CDs.練習(xí)： 1. Paragraphs 1 amp。 2 　　　　　　2. Paragraph 3 　　　　　　3. Paragraph 4 　　　　　　4. Paragraph 5 　　　　　　　　　　A Digital code has wide applications.　　　　B Floppy disks are outdated.　　　　C CDs are durable.　　　　D CD39。s working principle is explained.　　　　E CDRWs play better than CDROMs.　　　　F CDs are of many formats.　　5. One advantage of CDRWs is that they can __________ like floppy disks.　　6. The author predicts it will not __________ before a new technology is invented for music recording.　　7. The laser beamemitting device and the receiver are considered to __________ of a CD player.　　8. Space probes could not __________ without using digital codes.　　　　A shine on bumps　　　　B take many more years　　　　C be the key parts　　　　D restore the original code　　　　E be written on and rewritten on　　　　F keep contact with their ground station efficiently答案與題解：　　1. D第一、二段介紹了 CD 的工作原理。聲音以數(shù)碼的形式刻錄到CD碟片上。要回聽聲音，就得用 CD 放音機(jī)，CD 機(jī)用激光照射 CD，接收器收和分析從 CD 反射回來的激光波，還原為原來的數(shù)碼，再轉(zhuǎn)換為原來的聲音。所以，D 是答案?！　?. A　第三段第一句{Digital codes are used with many technologies.） 是主題句。 本段其它句子提供例證，即應(yīng)用領(lǐng)域。作者例舉了5個領(lǐng)域：電郵、航天通訊、條碼、手機(jī)和天氣預(yù)報。選項 A 的Digital code has wide applications與主題句的意思完全吻合，所以是答案?！　?. F　第四段第一句 （There are many types of pact disks} 是主題句。本段其它句子列舉了兩種常用的 CD 格式 （format）, 一種是 CDRW，另一種是 的CDs are of many formats概括了本段的大意，是答案?！　?. C　第五段說的是CD碟片經(jīng)久耐用，1982年上市的 CD 碟片至今還能使用，其音質(zhì)依舊?，F(xiàn)在上市的 CD，更加耐用，如果使用得當(dāng)，其壽命可達(dá)70－200年。選項 C 用了durable 予以概括是很恰當(dāng)?shù)?，所以，C是答案。　　5. E　第四段中出現(xiàn) CDRW 這個詞，介紹了They can be recorded on and rerecorded on （rewritten on）。這就是選 E 的依據(jù)?！　?. B　第六段能找到與答案有關(guān)的句子，即 It may not be many more years before a pletely new technology is invented and introduced to the public for music recording.　　7. C　第二段說到在 CD 機(jī)上還原數(shù)碼時依靠的是激光發(fā)射裝置和接收器。由此我們可以推論出激光發(fā)射器和接收器是 CD 機(jī)的主要部件。所以C是答案。　　8. F　第三段第三句 （Space probes municate with their ground station on earth using digital codes） 是選F的依據(jù)。第十一篇The Tiniest Electric Motor in the World recently made public the tiniest electric motor ever1 built. You could stuff hundreds of them into the period at the end of this sentence. One day a similar engine might power a tiny mechanical doctor that would travel through your body to remove your disease. motor works by shuffling atoms between two molten metal droplets in a carbon nanotube. One droplet is even smaller than the other. When a small electric current is applied to the droplets, atoms slowly get out of the larger droplet and join the smaller one. The small droplet grows but never gets as big as the other droplet and eventually bumps into the large droplet. As they touch, the large droplet rapidly sops up the atoms it had previously lost. This quick shift in energy produces a power stroke2. technique exploits the fact that surface tension the tendency of atoms or molecules to resist separating bees more important at small scales3. Surface tension is the same thing that allows some insects to walk on water. the amount of energy produced is small 20 microwatts it is quite impressive in relation to the tiny scale of the motor4. The whole setup5 is less than 200 nanometers on a side, or hundreds of times smaller than the width of a human hair. If it could be scaled up to the size of an automobile engine6, it would be 100 million times more powerful than a Toyota Camry39。s 225 horsepower V6 engine. 1988, Professor Richard Muller and colleagues made the first operating micromotor, which was 100 microns across7, or about the thickness of a human hair. In 2003, Zettl39。s group created the first nanoscale motor. In 2006, they built a nanoconveyor, which moves tiny particles along like cars in a factory. engineers try to mimic nature, building things atombyatom. Among other things, nanomotors could be used in optical circuits to redirect light, a process called optical switching. Futurists envision a day when nanomachines, powered by nanomotors, travel inside yur body to find disease and repair damaged cells. 詞匯：　　shuffle v. 來回運動　　nanometer n. 納米，毫微米　　molten adj. 熔化的　　micromotor n. 微電機(jī)　　droplet n. 小滴　　nanotube n. 納米管　　nanoconveyor n. 納米傳送帶　　nanotechnology n. 納米技術(shù)　　bump v. 碰撞　　mimic v. 模仿　　sop v. 吸入　　stroke n. 行程，沖程　　microwatt n. 微瓦　　nanomotor n. 納米發(fā)動機(jī)　　nanomachine n. 納米機(jī)器注釋：　　1. ever：比以往任何時候，曾經(jīng)。如：　　 This is the best book I have ever read.　　 （這是我讀過的書中最好的一本。）　　2. power stroke：動力行程　　3. at small scales：在小等級上。這里指的是 在納米等級上.　　4. it is quite impressive in relation to the tiny scale of the motor：與電動機(jī)的小等級相比，功率是相當(dāng)可觀了。in relation to 是與……相比.如：　　 The city is quite large in relation to its population.　　 （就人口而言，這個城市相當(dāng)?shù)拇?。）　?. setup：裝置。這里指 nanomotor.　　6. If it could be scaled up to the size of an automobile engine：如果納米電動機(jī)能按比例放大到汽車發(fā)動機(jī)的尺寸。scale…up to 是 把……按比例放大到…….　　7. across：從一端到另一端練習(xí)： 　　1. Paragraph 2 　　　　　　　　2. Paragraph 4 　　　　　　　　3. Paragraph 5 　　　　　　　　4. Paragraph 6 　　　　　　　　　　A　An introduction of a Toyota39。s 225 horsepower V6 engine.　　　　B　A description of the nanomotor in terms of power and size.　　　　C　Surface tension.　　　　D　Previous inventions of nanoscale products.　　　　E　The working principle of the nanomotor.　　　　F　Possible fields of application in the future.　　5. Doctors envision that the nanomotor would travel through human bodies to __________ .　　6. Surface tension means the tendency of atoms or molecules to __________ .　　7. Nanoconveyors could be __________ .　　8. Applying a small electric current causes atoms to __________ .　　　　A　remove disease　　　　B　resist separating　　　　C　shuffle between two molten metal droplets　　　　D　power nanomachines　　　　E　sop up molecules from the large droplet　　　　F　transport nanoscale objects答案與題解：　　1. E 第二段介紹了納米發(fā)動機(jī)的工作原理。兩小滴金屬熔液通上微弱電流，大的小滴的原子就會緩慢逸出，加入小的小滴，后者體積不斷增大，到一定階段，就會與前者碰撞，這時，大的小滴便奪回它失去的原子，這就是一次 po