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2017公共英语二级阅读文章

2017公共英语二级阅读文章

尽管2017年上半年的公共英语二级考试已经结束,但是不少的考生已经在为下半年的公共英语二级做准备了。小编这儿为大家整理了两篇2017公共英语二级阅读文章,供大家使用。

2017公共英语二级阅读文章

  2017公共英语二级阅读文章一

The modern age is an age of electricity. People are so used to electric lights, radio, televisions, and telephones that it is hard to imagine what life would be like without them. When there is a power failure, people grope about in flickering candlelight, cars hesitate in the streets because there are no traffic lights to guide them, and food spoils in silent , people began to understand how electricity works only a little more than two centuries ago. Nature has apparently been experimenting in this field for millions of years. Scientists are discovering more and more that the living world may hold many interesting secrets of electricity that could benefit humanity.

All living cells send out tiny pulses of electricity. As the heart beats, it sends out pulses of record; they form an electrocardiogram, which a doctor can study to determine how well the heart is working. The brain, too, sends out brain waves of electricity, which can be recorded in an electroencephalogram. The electric currents generated by most living cells are extremely small —— often so small that sensitive instruments are needed to record them. But in some animals, certain muscle cells have become so specialized as electrical generators that they do not work as muscle cells at all. When large numbers of these cells are linked together, the effects can be astonishing.

The electric eel is an amazing storage battery. It can send a jolt of as much as eight hundred volts of electricity through the water in which it lives. (An electric house current is only one hundred twenty volts.) As many as four-fifths of all the cells in the electric eel's body are specialized for generating electricity, and the strength of the shock it can deliver corresponds roughly to the length of its body.

当今时代是电气时代。人们对电灯、收音机、电视和电话早已司空见惯以致很难想象没有它们生活会变成什么样。当停电时,人们在摇曳不定的烛光下暗中摸索;因没有红绿灯的指示,汽车在道路上迟疑不前;冰箱也停止工作,导致食物变质。人们只是在两个世纪前一点才开始了解电的使用原理,自然界却显然在这方面经历过了数百万年。科学家不断发现许多生物世界里可能有益于人类的关于电的有趣秘密。所有生物细胞都会发出微小的电脉冲。当心脏跳动时,把它发出的脉冲记录下来就成了心电图,这可让医生了解心脏的工作状况。大脑也发出脑电波,这可在脑电图上记录下来。许多生物细胞发出的电流都是极微小的,小到要用灵敏仪器才能记录和测量。但一些动物的某些肌肉细胞能转化成一个个发电机,以致完全失去肌肉细胞的功能。这种细胞大量地连接在一起时产生的效果将是非常令人吃惊的。电鳗就是一种令人惊异的蓄电池。它可以在水中发出相当于800伏特电压电流(家庭用户的电压只有120伏特)。在电鳗的身体里,多至五分之四的细胞都专门用来发电,而且发出的`电流的强度大约和它身体的长度成正比。

  2017公共英语二级阅读文章二

Television —— the most pervasive and persuasive of modern technologies, marked by rapid change and growth —— is moving into a new era, an era of extraordinary sophistication and versatility, which promises to reshape our lives and our world. It is an electronic revolution of sorts, made possible by the marriage of television and computer technologies.

The word "television", derived from its Greek (tele: distant) and Latin (visio: sight) roots, can literally be interpreted as sight from a distance. Very simply put, it works in this way: through a sophisticated system of electronics, television provides the capability of converting an image(focused on a special photoconductive plate within a camera) into electronic impulses, which can be sent through a wire or cable. These impulses, when fed into a receiver (television set), can then be electronically reconstituted into that same image.

Television is more than just an electronic system, however. It is a means of expression, as well as a vehicle for communication, and as such becomes a powerful tool for reaching other human beings.

The field of television can be divided into two categories determined by its means of transmission. First, there is broadcast television, which reaches the masses through broad-based airwave transmission of television signals. Second, there is nonbroadcast television, which provides for the needs of individuals or specific interest groups through controlled transmission techniques.

Traditionally, television has been a medium of the masses. We are most familiar with broadcast television because it has been with us for about thirty-seven years in a form similar to what exists today. During those years, it has been controlled, for the most part, by the broadcast networks, ABC, NBC, and CBS, who have been the major purveyors of news, information, and entertainment. These giants of broadcasting have actually shaped not only television but our perception of it as well. We have come to look upon the picture tube as a source of entertainment, placing our role in this dynamic medium as the passive viewer.

以快速变化与发展为标志的最普遍、最具有影响力的一项现代技术,正在步入一个极端复杂化与多样化的新时代。这个时代承诺重新塑造我们的生活和我们的世界。这可以称得上是又一次电子革命,其关键在于电视技术与计算机技术的结合。

“电视”这个词来源于希腊语词根(tele:远)和拉丁语词根(vision:景象),可以从字面上理解为来自远处的景象。简单说来,电视是以这种方式工作的,通过一个复杂的电子系统,电视能够将一幅图像(这幅图像被聚焦在一部摄像机内的一块特殊的光导底片上)转换成能经过导线或电缆发送出去的电子脉冲信号。当这些电子脉冲信号被输入一部接收机(电视机)时,就可以用电子学的方法把脉冲信号重新恢复成同一幅图像。

但是,电视不仅仅是一个电子系统,它还是一种表达工具和传播渠道。因此,电视成了一个对其他人发生影响的强大工具。

电视这个领域可以根据其发射方式分为两类。第一类为广播电视,通过电视信号的宽带无线电波发射展现在大众面前;第二类为非广播电视,使用受控的发射技术来满足个人以及某些特殊利益群体的需要。

电视早已成为大众媒介。我们熟悉广播电视,因为广播电视已经以类似目前的方式存在了大约37年。在那些年头中,电视绝大部分一直由ABC、NBC、CBS这些广播电视公司控制着,这些广播电视公司一直是新闻、信息和娱乐的主要提供者。这些广播业的巨头实际上不仅塑造了电视,而且也塑造了我们对电视的理解。我们渐渐把显像管看作是娱乐的来源,让自己成为这个生动的媒介的被动观众。、NBC、CBS这些广播电视公司控制着,这些广播电视公司一直是新闻、信息和娱乐的主要提供者。这些广播业的巨头实际上不仅塑造了电视,而且也塑造了我们对电视的理解。我们渐渐把显像管看作是娱乐的来源,让自己成为这个生动的媒介的被动观众。

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