Electric Backpack
1. Backpacks（背包） are convenient. They can hold your books, your lunch, and a change of clothes, leaving your hands free to do other things. Someday, if you don’t mind carrying a heavy load, your backpacks might also power your MP3 player, keep your cell phone running, and maybe even light your way home.来源：中国职称英语考试网
2. Lawrence C. Rome and his colleagues from the University of Pennsylvania in Philadelphia（费城[美国宾夕法尼亚州东南部港市]） and the Marine Biological Laboratory in Woods Hole（美国马萨诸塞州的一个渔村，也是许多重要研究机构所在地）, Mass（Massachusetts 的缩写：马萨诸塞州，美国东北部的一个州）
）have invented a backpack that makes electricity from energy produced while its wearer walks. In military actions, search-and-rescue operations, and scientific field studies, people rely increasingly on cell phones, global positioning system (GPS)（全球定位系统） receivers（接收机）, night-vision goggles（夜视镜）, and other battery-powered devices to get around and do their work.. The backpack’s electricity-generating feature could dramatically reduce the amount of a wearer’s load now devoted to spare batteries, report Rome and his colleagues in the Sept. 9 Science6.
3. The backpack’s electricity-creating powers depend on springs used to hang a cloth pack from its metal frame. The frame sits against the wearer’s back, and the whole pack moves up and down as the person walks. A gear mechanism converts vertical（垂直的） movements of the pack to rotary （旋转的）motions of an electrical generator, producing up to 7.4 watts（瓦（特））.
4. Unexpectedly, tests showed that wearers of the new backpack alter their gaits（步态，步法） in response to the pack’s oscillations（摆动） so that they carry loads more comfortably and with less effort than they do ordinary backpacks. Because of that surprising advantage, Rome plans to commercialize（商业化） both electric and non-electric versions of the backpack.
5. The backpack could be especially useful for soldiers, scientists, mountaineers（登山运动员）, and emergency workers who typically carry heavy backpacks. For the rest of us, power-generating backpacks could make it possible to walk, play video games, watch TV, and listen to music, all at the same time. Electricity-generating packs aren’t on the market yet, but if you do get one eventually, just make sure to look both ways before crossing the street!
Questions:
3. The word “springs” in Paragraph 3 means ____________.
A) a small stream of water flowing naturally from the earth.
B) the season of the year, occurring between winter and summer.
C) the act or an instance of jumping or leaping.
D) a length of metal wound around, which returns to its original shape after being pushed.
4. According to Paragraph 4, what does Rome plan to do?
A) To make the backpack more comfortable for the wearer.
B) To put the backpack on the market.
C) To test the advantage of the backpack.
D) To promote the backpack in a newspaper or on television.
5. What is implied in “if you do get one eventually, just make sure to look both ways before crossing the street!”
A) You will be too excited to watch the traffic.
B) Enjoying electronic devices while walking may invite traffic accidents.
C) It is not possible for you to get such a backpack.
D) It is wise of you to have such a backpack.
文章详解：
4.让我们继续看第三题：
3. The word “springs” in Paragraph 3 means ____________.
A) a small stream of water flowing naturally from the earth.一小股自然流淌的水流（泉水）
B) the season of the year, occurring between winter and summer.一年中的一个季节，介于冬季和夏季之间（春天）
C) the act or an instance of jumping or leaping. 突然跳起来（蹦）
D) a length of metal wound around, which returns to its original shape after being pushed. 来回绕的一段金属，在被挤压后能回复它的原形（弹簧）
这种题型属于曾经介绍过的单词释义题，通常所面对的词汇是多义词，但要通过它出现的上下文，猜测出它的含义。Spring当动词时，意思是蹦、跃起；当名词讲，是泉水、弹簧、发条、春天等。让我们看看文章里含有该词的句子：
The backpack’s electricity-creating（产生的） powers （能量）depend on springs used（被用来） to hang（挂） a cloth pack（布包） from its metal frame（金属框架）.
所以，可以推断spring只能当弹簧讲，因此答案是D。
The frame sits（搁、放） against （倚、靠）the wearer’s back, and the whole pack（包） moves up and down（上下移动） as（当） the person walks. A gear （）mechanism（机械装置） converts（转化） vertical（垂直的） movements of the pack to rotary （旋转的）motions（运动） of an electrical generator（电子发电机）, producing up to（多达） 7.4 watts（瓦，电功率单位）.来源：中国职称英语考试网
5．第四题：
4. According to Paragraph 4, what does Rome plan to do?
A) To make the backpack more comfortable for the wearer.为了使背包对于背的人来说更舒适
B) To put the backpack on the market. 为了把背包推向市场
C) To test the advantage of the backpack. 为了检测背包的优点
D) To promote the backpack in a newspaper or on television.为了在报纸上或电视上促销背包。
题目的意思是；根据第四段，罗马计划要做什么？又是细节题。
Unexpectedly（出人意料的是）, tests （实验）showed that wearers of the new backpack alter（同义词change, 改变）their gaits（步态，步法） in response to（响应、配合）the pack’s oscillations（摆动） so that （引导目的状语从句，表示“为了”）they carry（携带） loads（重物、重量） more comfortably and with less effort（更少的力量） than they do ordinary（普通的） backpacks. Because of that surprising（令人吃惊的） advantage（优点、优势）, Rome plans（动词，计划） to commercialize（使。。。商业化） both electric（电子的） and non-electric（非电子的） versions （种类）of the backpack.
最后一句是答案的出处，即Rome计划将这种背包商业化，即，推向市场。
所以，答案是B。来源：中国职称英语考试网
6．看最后一个问题：
5. What is implied in “if you do get one eventually, just make sure to look both ways before crossing the street!”
A) You will be too excited to watch the traffic. 你会太兴奋以至于不注意来往车辆。
B) Enjoying electronic devices while walking may invite traffic accidents.
一边走一边享受电子设施有可能会导致意外。
C) It is not possible for you to get such a backpack.你不可能得到这样一个背包。
D) It is wise of you to have such a backpack. 拥有这样一个背包对你来说是明智的。
题目的意思是：“如果你终于得到这样的背包，过马路时一定要两面都看看。”这句话根据提问方式是推理题：即，根据文章已有的信息或文章的含义进行归纳和总结；或推断文章的引申、暗示的含义；
我们一起看最后一段：
The backpack could be especially（尤其） useful（有用的） for soldiers（士兵）, scientists, mountaineers（登山运动员）, and emergency workers （对紧急情况进行处理的工作人员）who typically（特别地、独特地） carry heavy backpacks. For the rest of us（对于我们其余人而言）, power-generating backpacks could make it （形式宾语）possible to walk, play video games（玩游戏）, watch TV, and listen to music, all at the same time（同时间进行）. Electricity-generating packs aren’t on the market （还没有出现在市场上）yet, but 5>.if you do get one eventually, just make sure to look both ways before crossing the street!
我们也知道，凡事既有利又有弊。通过读这篇文章，我们知道电子背包有很多的优点，但当我们一边走路，一边玩着游戏、听着音乐、看着电视，就有可能会导致交通意外的发生。所以答案就是B。
