托福獨立寫作考生無非三大難題：沒思路，不會寫，寫不好。其實，思路的拓展和常用表達的積累都可以通過一些英文材料的精讀仿寫達成，下面我們就來看一篇和科技類有關的雙語素材和相關核心詞匯句式梳理。
Electronics has already cut the data cord. Can it now cut the power cord as well?
電源線會和數據線一樣慢慢消失嗎?
Jun 27th 2015 | Seattle | From the print edition
Wireless Power-transmission
DRONES may one day transform the way parcels are delivered, crops monitored and suspects apprehended. Those who talk up these possibilities, though, often neglect to mention the drawbacks of such robot aircraft—one of which is that most cannot fly for more than a quarter of an hour before they need to find a human being to swap their batteries for them or plug them into an electrical socket.
無人機沒準兒有一天會給我們生活的方方面面都帶來巨大的改變，無論是包裹投遞，還是農作物監控，甚至是抓捕嫌犯。然而大談特談這些可能性的人們卻忽略了無人駕駛飛機的弊端，其中一個就是他們需要定期的由人來更換電池或者充電。
Joshua Smith, a computer scientist at the University of Washington, in Seattle, hopes to change that. In May he started a company called Wibotic that plans to recharge drones (and also earthbound robots) without them having to establish an awkward physical connection with a plug. A ’bot whose batteries were low would simply manoeuvre itself to within half a metre or so of a recharging station to top them up. LaserMotive, another Seattle-based company, is even more ambitious. It is developing a system designed to replenish the batteries of drones that are still aloft, using lasers and photovoltaic cells.
只要有問題或者有需求就會有人想去改變，無人機用途那么廣，總需要人來充電哪行?于是華盛頓大學一個哥們 JS 就搞了個公司 Wibotic，主要目的就是讓無人機無需通過物理連接充電，否則那多尷尬啊，飛著飛著還得找個地方插上線充電，感覺特別low，如果能在空中無需通過物理連線就把電沖了就爽了，Wibotic 和 LaserMotive 這兩家公司主要就是想實現無人機無線充電。
The idea of wireless power-transmission of this sort goes back more than a century. In 1893 Nikola Tesla (pictured), who was one of the pioneers of industrial-scale electricity, illuminated light bulbs across a room in a demonstration at the Columbian Exposition in Chicago. And that was a mere fleabite compared with his grander ambitions. He claimed to believe it possible to broadcast power around the world using a system of towers and balloons, and even convinced J.P. Morgan to back a trial.
事實上，無線充電這個想法本身是比較老的，1893年大神特斯拉就提出了一個非常牛逼的想法：通過塔和氣球在全球傳播能量，還贏得了摩根的投資。讀了這個我很困惑就去查了一下，這個瘋狂的哥們是這么想的：
He theorized from these experiments that if he injected electric current into the Earth at just the right frequency he could harness what he believed was the planets own electrical charge and cause it to resonate at a frequency that would be amplified in "standing waves" that could be tapped anywhere on the planet to run devices or, through modulation, carry a signal.
大致意思可能是這樣的(完全不懂)：將電流以正確的頻率注入地球，然后在全球任意一個地方都可以用來運行裝置或者傳遞新號!
That failed, as most other physicists of the time predicted it would. More modest remote power-transmission is, however, now attracting attention again. The technology Tesla pioneered is already being used to charge mobile phones, and researchers are working on similarly wirelessly powered kitchen appliances, military equipment such as heads-up displays, and medical devices ranging from heart pumps to brain monitors.
這個想法失敗了，正如大部分其他的物理學家預測的那樣。但是特斯拉提出來的概念現在正在被廣泛的用來給各種東西充電：手機、加點、軍事裝備以及醫療設備等等。
Working Principles
Lasers aside, the principle behind most wireless power-transmission is a piece of basic physics known asinduction. In this process an alternating current passing through a coiled wire creates an oscillating magnetic field. That field then induces another alternating current in a second, nearby coil. If the transmitting and receiving coils are close together and aligned in the same direction, almost all of the power will be transmitted.
大部分無線能量傳輸原理都是電磁感應。交流電通過線圈會產生震蕩磁場，這個磁場會在附近的線圈中產生另一個交流電場。如果發送端和接收端的線圈足夠近、方向對齊的話，能量傳輸率為100%。
Inductively coupled systems like this thus work well for things like repowering electric toothbrushes. They would be impractical, though, for a drone trying to hover over a charging station. Wibotic’s answer is to use tuned electrical circuits in place of simple transmitting and receiving coils. When such circuits are tuned to the same resonant frequency, they exchange energy more efficiently.
電感耦合系統用來給電動牙刷啥的充電還行，給無人機充電不現實，因為無人機并不是靜止的。所以可能需要將簡單的傳輸電路改為調制電路來提高能量傳輸效率。
For remote charging to take off metaphorically as well as literally, though, devices employing it need to be interoperable. That means establishing industry standards. Unfortunately, in a competitionreminiscent of that in the 1890s between alternating current (Tesla’s preference) and direct current (promoted by Thomas Edison), three main consumer standards have emerged.
遠程充電要想成為現實，相關的設備必須是可以相互操作的，也就意味需要統一的工業標準。然而不幸的是，現在已經出現了三個這樣的標準，正如當年的交流直流之爭一樣，誰也不甘讓步。
The Tesla exception
The rise of electric cars opens yet another market for remote power-transmission. Carmakers are keen to avoid the standards war that has broken out among makers of smaller gadgets. If convenientwireless charging lets carmakers halve the size of electric-vehicle batteries, it could slashthousands of dollars from their prices. That would make a huge difference to the economics of owning and running them. Nikola Tesla failed to beam power between continents but his tricks may yet succeed in something equally dramatic: decarbonising the world’s road vehicles.
遠程能量傳輸用在電動汽車上挺牛逼的，充電根本都不用下車了，就跟找熱點一樣，找到了一對齊就自動開始沖了。汽車制造商才不管什么標準呢，你們吵你們的，我們做我們的。如果無線充電能夠實現，汽車電池就能變小一半，價格也會隨之大大下降。電動汽車勢必變得更加有吸引力。特斯拉可能又對人類做出了一個新的貢獻，那就是給路上的車輛除碳。
句型練習
原句：
Those who talk up these possibilities, though, often neglect to mention the drawbacks of such robot aircraft—one of which is that most cannot fly for more than a quarter of an hour before they need to find a human being to swap their batteries for them or plug them into an electrical socket.
推薦句型:
Those who talk up the benefits of X, though, often neglect to mention the drawbacks of X one of which is that...
那些大談特談X的好處的人通常忽略X的缺點，其中一個就是...
原創例句：
Those who talk up the benefits of the Internet, though, often neglect to mention the drawbacks of the ubiquitous network connection one of which is that our private information is highly likely to be compromised by data breach caused by malicious hackers.
想必大家也都看到新聞了哈，最近老美不是一直在埋怨，中國的黑客入侵他們的各種系統，獲取各種數據，可是都只是停留在聲討，因為他們貌似并沒有啥證據。
翻譯練習：
那些大談特談城市擴張的好處的人通常忽略混亂的城市化模式的弊端，其中一個就是作為資產擁有者的城市中產階級和外來移民構成的底層階級之間的日益增大的差距可能會導致很多社會問題。
歡迎大家點擊“閱讀原文”完成句子練習，只要按要求完成了就可以獲得批改并收到參考答案哈!!!
重點表達
swap：交換、互換
gadget：小器具、小裝置
harness：利用
replenish：補充、重新裝滿
slash：大大降低
manoeuvre：調動、機動
decarbonise：去碳
fleabite：少量的花費
reminiscent：使...想起過去
resonate：產生共鳴
induction：感應現象
electric current：電流
alternating current：交流電
wireless charging：無線充電
make a huge difference to：使產生很大的不同
coiled wire：線圈
data cord：數據線
power cord：電源線
electrical charge：電荷
medical device：醫療設備
heart pump：心臟泵
brain monitor：大腦監測器
electric toothbrush：電動牙刷
electric car：電動汽車
industry standard：工業標準
oscillating magnetic field：震蕩磁場
electric-vehicle battery：電動汽車電池
top up：充
inject into：射人
hover over：盤旋
recharging station：充電站
wireless power-transmission：無線電能傳輸
open a market for：打開市場
are keen to：熱衷于
plug them into an electrical socket：插入電源插座
establish an awkward physical connection with a plug：和插座建立尷尬的鏈接
