从课文中.我们可以推出作者的意图是要说明 . ［A］ 我们技术的局限性 ［B］ 宇宙现实的广阔性 ［C］ 星际旅行的前景 ［D］ 时间和空间对心理上的影响 ［精解］ 答案C本题考查写作目的.综观全文.作者从无线电和光速谈起.批评了很多持保守态度的人.进而论证人类终将跨越宇宙鸿沟.文章最后描述未来星际旅行标志了人类跨越宇宙鸿沟的实现.可见.［C］是作者要说明的问题. 全文翻译 神奇的电话和电视网络将整个世界连结在一起.使所有的人都成了邻居.但是却不能延伸到宇宙中.你永远不可能和另一个星球上的人进行对话.即使有今天的无线电设备.信息传播也需要好几分钟.有时候甚至好几个小时.因为无线电和光波都是以每秒186, 000英里的有限速度传播. 20年后你能够听来自火星上的朋友说话.但是话从他口中说出至少要经过三分钟你才可以听到.你的回答也将经过相同的时间才能到达他耳中.在这样的状况下.交换语言信息是可能的.但是不可能对话. 对于一个认为即刻交流理所当然.并将其视为文明生活完整结构的一部分的文化来说.这种“时间障碍 可能会有深刻的心理影响.时间障碍(即无法和外星人进行对话)永远提醒我们不是所有的技术都能战胜普遍规律和限制.看起来非常确定的事情是:没有信号.更不用说物质.可以比光传播的速度快. 作为时空结构的一部分.光速是终极速度极限.在太阳系狭小的范围内.它不会给我们带来太严重的不便.最糟糕的情况也就是20小时.即无线电信号越过最远的冥王星的轨迹的时间. 正是当我们走到太阳系的界限之外的时候.我们开始面对着一个全新的宇宙秩序.即使在今天.许多在别的方面受过教育的人.像只能数到三而把三以上的数字都统称为四的野人.他们无法明白太阳系和恒星系的巨大不同.前者是围绕我们邻近的世界即行星的宇宙.后者是围绕那些遥远的恒星的宇宙.确实大几百万倍.地球上的事物在规模上没有这样巨大的变化. 许多保守的科学家惊讶于这些宇宙鸿沟之大.因此否认跨越它们的可能性.有些人永远也不会进步:他们60年前怀疑飞行的可能性.10年前耻笑飞往其他行星的想法.现在又满有把握地说恒星是我们永远不能及的.他们再一次地错了.因为他们没有领悟我们这一时代的教训--如果某些东西从理论上说是可能的.并且没有一些基本的科学法则反对它的实现的话.它早晚都会实现. 有一天.我们会发现一种真正有效的航天器驱动方式.每一个技术发明都会发展到极限.而宇宙飞船的最终速度是光速.它们永远不会达到这个速度.但是它们将会与这个速度非常接近.那时.离地球最近的恒星用不了5年就可以到达. Text 4 One great benefit of the Web is that it allows us to move information online that now resides in paper form. Several states in America are using the Web in a profound way. You can apply for various permits or submit applications for business licences. Some states are putting up listings of jobs-not just state government jobs, but all the jobs available in the state. I believe, over time, that all the information that governments print, and all those paper forms they now have, will be moved on to the Internet. Electronic commerce notches up month-by-month too. It is difficult to measure, because a lot of electronic commerce involves existing buyers and sellers who are simply moving paperbased transactions to the Web. That is not new business. Microsoft, for example, purchases millions of dollars of PCs online instead of by paper. However, that is not a fundamental change; it has just improved the efficiency of an existing process. The biggest impact has occurred where electronic commerce matches buyers and sellers who would not previously have found each other. When you go to a book site and find an obscure book that you never would have found in a physical bookstore, that is a new type of commerce. Today, about half of all PCs are still not connected to the Web. Getting communications costs down and making all the software simpler will bring in those people. And that, in turn, will move us closer to the critical mass that will make the Web lifestyle everyone's lifestyle. One element that people underestimate is the degree to which the hardware and software will improve. Just take one aspect: screen technology. I do my e-mail on a 20-inch liquid crystal display (LCD) monitor. It is not available at a reasonable price yet, but in two years it will be. In ten years, a 20-inch LCD with much higher resolution will be commonplace. The boundary between a television set and a PC will be blurred because even the set-top box that you connect up to your cable or satellite will have a processor more powerful than what we have today in the most expensive PC. This will, in effect, make your television a computer. Interaction with the Web also will improve, making it much easier for people to be involved. Today the keywords we use to search the Web often return to too many articles to sort through, many of them out of context. If you want to learn about the fastest computer chip available, you might end up getting responses instead about potato chips being delivered in fast trucks. In the future, we shall be either speaking or typing sentences into the computer. If you ask about the speed of chips, the result will be about computers, not potatoes. Speech recognition also means that you will be able to call in on a phone and ask if you have any new messages, or check on a flight, or check on the weather. To predict that it will take over ten years for these changes to happen is probably pessimistic. We usually overestimate what we can do in two years and underestimate what we can do in ten. It will not be too long before the Web becomes as much a way of life as the car.［558 words］ 【查看更多】
