科技英语文章翻译
科技英语课文翻译
Unit 1大规模研究发现：地球的“健康”每况愈下有史以来对地球进行的最大规模的科学分析结果表明，地球上的许多生态系统都达不到标准。
由联合国主持的《千年生态系统评估综合报告》指出，由于不可持续的使用，地球上将近三分之二的用来维持生命的生态系统（包括干净的水源、纯净的空气以及稳定的气候）正遭受破坏。
以上大部分的破坏都是人类在过去的半个世纪里造成的。
据报告分析，随着人类对食物、淡水、木材、纤维以及燃料等资源的需求日趋激增，环境发生了极大的变化，引发了诸如滥伐森林、化学污染等问题。
因此，该报告的作者警告说，照此下去，本已岌岌可危的生态环境将会在21世纪的上半叶进一步恶化。
这项历史性的研究由来自世界95个国家的政府部门以及民间组织的1,300多位科学家共同完成。
四年来，他们考察了地球上许多生物的生长环境、物种以及将他们联系起来的生态体系。
联合国环境规划署对该报告进行了编辑整理并于昨天在中国北京公布了研究结果。
在公布该报告的新闻发布会上，联合国秘书长科菲·安南指出：“只有了解环境及其运作过程，我们才能制定出必要的措施加以保护它。
”他还说，“只有珍惜所有宝贵的自然资源和人类资源，我们才有希望去建设一个可持续发展的未来。
”对社会经济的影响该报告对自然界的大部分生物多样性持悲观态度，地球上可能有10%—30%的哺乳动物，鸟类以及两栖动物濒临灭绝。
这次大规模生态调查是根据安南的《千年发展目标》展开的，该发展目标是由联合国发起的，旨在2015年之前大幅减少饥饿与极度贫困等社会经济问题。
总部位于内罗毕的联合国环境规划署执行主席克劳斯·托普弗说：“从某些方面来说，《千年生态系统评估综合报告》让我们首次认识到生态系统服务功能的经济价值，并使我们对尊重和保护地球生命维护系统有了新的见解。
”目前由于人类社会对地球环境的开发利用，食物供应不断增加，然而增长的速度仍然太慢，难以完成联合国制定的在2015年之前消除全球一半饥饿人口的目标。
科技英语阅读与翻译
科技英语阅读与翻译【牙齿仙女】Primitive peoples believe that hair， nail clippings， and lost teeth remain magically linked to the owner even after they have been disconnected from his body. As any voodoo artist will tell you， if you want to grind someone into powder， you don't need to touch him at all. It's quite enough to stamp on a missing molar and let ;contagious magic; do the rest. This is why peoples all over the world traditionally hide lost body parts， lest they fall into the wrong hands.远古时期的人们认为毛发、剪下的指甲和脱落的牙齿即使离开了人的身体，仍与其主人保持着神秘的联系。
正如任何一个伏都教大师都会告诉你的，假如你想置某人于死地，根本用不着去碰他，只需用脚踩碎那人脱落的一颗臼齿就够了，剩下的事就交给无边的法力去办。
这就是为什么全世界各个民族都习惯于把身体上脱落的东西藏起来，以免落入恶人之手。
American children's ritual of hiding lost teeth under their pillows probably derives distantly from this practice. But there is an obvious difference， for when Suzie conceals her baby milk-tooth， she fully expects it to be found， and by a good magician， not an evil one. Moreover， she expects to be paid for having surrendered it， and at the going rate. Nothing mare clearly suggests the blithe commercial gusto of our culture than this transformation of a fearful superstition into a cheery business transaction。
科技英语 主编 田文杰 课文翻译
Unit 1Artificial intelligence is the science and engineering of making intelligent machines,especially intelligent computer programs.人工智能是制造智能机器的科学与工程，特别是智能化的计算机程序。
It is related to the similar task of using computers to understand human intelligence,but AI does not have to confine itself to methods that are biologically observable.这与使用计算机来理解人类智能的类似任务有关，但是人工智能不需要把它局限在生物可观察的方法上。
In this unit,the two passages present a general picture of AI research .在这个单元，两个章节提出了人工智能研究的概况。
Text A briefly introduces the definition of AI,some kinds of architectures of AI system,essential capabilities to AI programs and so on.文章A简要介绍了人工智能的定义，人工智能的系统的几种体系结构、基本功能以及程序等等。
Text B explains a particular area of AI research--natural language processing including its definition and a legendary Turing’s Test.文章A解释特定地区研究人工智能的自然语言处理包括定义和传说中的图灵测试。
科技的利弊英语作文带翻译
科技的利弊英语作文带翻译科技的利弊英语作文带翻译在平平淡淡的学习、工作、生活中，许多人都有过写作文的经历，对作文都不陌生吧，借助作文可以提高我们的语言组织能力。
那么你有了解过作文吗？以下是店铺整理的科技的利弊英语作文带翻译，欢迎大家借鉴与参考，希望对大家有所帮助。
科技的利弊英语作文带翻译篇1科技是把双刃剑Improvement in science and technology is a double-edged sword, offering comfort and convenience to life, while simultaneously bringing harm and pain to people.When the development of science and technology brings mankind plenty of profits, it also brings us severely negative effects.积极影响：positive effects高科技对人类社会发展的积极影响1、促进了社会生产力的迅速发展。
New scientific discovery and technical revolution are changing the social mode of production, promoting the development of the social productivity2、提高了人们的物质和精神文化生活水平。
With the rapid development of science and technology,people's material and spiritual life have been greatly improved现代科技成果广泛应用,使人们的'闲暇生活变得丰富多彩，例如上网游戏，听音乐，看电影等。
科技英语课文翻译
科技英语课文翻译课文翻译英语Unit 1罗素悖论的提出是基于这样的一个事例：设想有这样一群理发师，他们只给不给自己理发的人理发。
假设其中一个理发师符合上述的条件，不给自己理发；然而按照要求，他必须要给自己理发。
但是在这个集合中没有人会给自己理发。
（如果这样的话，这个理发师必定是给别人理发还要给自己理发）1901年，伯特兰罗素悖论的发现打击了他其中的一个数学家同事。
在19世纪后期，弗雷格尝试发展一个基本原理以便数学上能使用符号逻辑。
他确立了形式表达式（如：应。
一种类比是救护车的汽笛声会改变音高――当它朝你行驶，然后通过你身边接着朝另一个方向去了的时候――他的声波首先是压缩的，接着伸长这些测量给了天文学家一个关于宇宙在不同历史点的膨胀速度的图景。
研究人员还发现宇宙如今正在以前所未有的速度在膨胀。
“一开始我们不情愿相信我们的结果，”加州大学伯克利分校的劳伦斯伯克利实验室的天体物理学家Saul Perlmutter说，他领导的一个竞争性的小组发现了和Schmidt以及Riess 相同的结果。
x =2）和数学特性（如偶数）之间的联系。
按照弗雷格理论的发展，我们能自由的用一个特性去定义更多更深远的特性。
1903年，发表在《数学原理》上的罗素悖论从根本上揭示了弗雷格这种集合系统的局限性。
型的集合系统能很好的用俗称集的结构式来描述。
就现在而言，这种类们可以用x代表整数，通过n来表示并且n大于3例如，小于我7，来表示x={n4，5,6这样一个集合。
这种集合的书写形势就是：我们也可让：n是整数，y={x：3n7}x是美国的一个男性居民。
集合中的对象并不一定是数字。
}。
求的空间。
但是，罗素（和策梅洛一起）发现表面上看，似乎任何一个关于x的描述都有一个符合要a中}导致一个矛盾，就像对一群理发师的描述一样。
x={a：xa它本不再身是在x有致命的打击。
尽管这样，他还不能解决这个问题当罗素发现了悖论，的集合中吗？否定的答案导致了矛盾的出现。
科技英语阅读翻译
Before any evidence can be introduced in support of the topic at hand, thedefinition of invention must be established. Legally, an invention is a new, useful, and non-obvious process, machine, or product . Maurice Fabre, author of A History of Land Transportation(1963), offered an interesting take on the automobile and its inventor . "who, for that matter ,can say who invented thewith his steam carriage of 1801, or Benz or Daimler with their first successfulcars of 1886?depends what you meanby an automobile ." in the year 2001, what do we consider the automobile to be ?I invite the reader to take a minute to look out the window . I see a street linedwithcars . Many of these cars possess similar shapes and sizes . Infact, some ofthem are the same make and model, only different colors . What does this tell us about the modern automobile?The modern automobile is not a single vehicle;itfact, we could argue that the modernautomobile is a giant technological systemthatEngineers design the components,manufacture the components,assemblers the components into complete systems,truck driversdeliver the assembled product, and salesmen sell the product to the masses . This brieflogistics and maintain financial accounts,or the separate companies that mine raw materials or design and manufacture the needed machine tools . What would the economy of the United States be like without the modern automobile?Obviously, the modernautomobile and self propelled vehicle are necessarily thesame .翻译：在任何证据被介绍来支持这个主题以前，必须建立发明的定义。
科技英语阅读翻译
1all elements are composed of scattered units called atoms,which are the smallest particles than show the characteristics of the element. atoms are tiny units of matter composed of positively charged protons, negatively charged elements ,and electrically neutral neutrons. protons and neutrons, which have almost the same mass,are clustered in the nucleus in the middle of the atom. electrons,which are tiny in comparison to the other units, move around the nucleus at high speed. atoms that have the same number of electrons and protons are electrically neutral. those that have got or lost electrons,and therefor are positively or negatively charged, are called ions.所有的元素都称为原子的散射单元，这是比显示的元件的特性的最小的颗粒组成。
原子是微小单位的物质组成的带正电的质子，带负电荷的元件和电中性的中子。
质子和中子，它们具有几乎相同的质量，聚集在细胞核内的原子在中间。
的电子，这在其他单位相比是微小的，围绕原子核高速移动。
具有相同的电子和质子数的原子是电中性的。
科技英语中英文对照翻译
mobile and cellular radio移动和细胞广播in comparison to the relative stability and modest technical developments which are occurring in long haul wideband microwave communication systems there is rapid development and expanding deployment of new mobile personal communication system. These rang from wide coverage area pagers,for simple data message transmission,which employ common standards and hence achieve contiguous coverage over large geographical areas,such as all the major urban centres and transport routes in Europe,Asia or the continental USA.This chapter discusses the special channel characteristics of mobile systems and examines the typical cellular clusters adopted to achieve continuous communication with the mobile user.It then highlights the important properties of current,and emerging,TDMA and code division multiple access(CDMA), mobile digital cellular communication systems.Private mobile radioTerrestrial mobile radio works best at around 250 MHz as lower frequencies than this suffer from noise and interference while higher frequencies experience multipath propagation from buildings,etc,section 15.2.In practice modest frequency bands are allocated between 60MHz and 2GHz. Private mobile radio(PMR) is the system which is used by taxi companies,county councils,health authorities,ambulance services,fire services,the utility industries,etc,for mobile communications.PMR has three spectral at VHF,one just below the 88 to 108 MHz FM broadcast band and one just above this band with another allocation at approximately 170MHz.There are also two allocations at UHF around 450MHz. all these spectral allocations provide a total of just over 1000 radio channels with the channels placed at 12KHz channel spacings or centre frequency offsets. Within the 12khz wide channal the analogue modulation in PMR typically allows 7khz of bandwidth for the signal transmission.when further allowance is made for the frequency drift in the oscillators of these systems a peak deviation of only 2 to 3 khz is available for the speech traffic. Traffic is normally impressed on these systems by amplitude modulation or frequency modulation and again the receiver is of the ubiquitous superheterodyne design,Figure 1.4. A double conversion receiver with two separate local oscillator stages is usually required to achieve the required gain and rejection of adjacent channel signals.One of the problems with PMR receiver is that they are requiredto detect very small signals,typically—120dBm at the antenna output,corresponding to 0.2 uV,and,after demodulating this signal,produce ann output with perhaps 1W of audio equipment, the first IF is normally at10.7MHz and the second IF is very orten at 455KHz . unfortunately,with just over 1000 available channels for the whole of the UK and between 20000and30000issued licences for these systems,it is inevitable that the average busuness user will have to share the allocated channel with other companies in their same geographical area.There are various modes of operation for mobile radio communications networks, the simplest of which is singal frequency simplex. In simplex communication, traffic is broadcast, or one way. PMR uses half duplex(see later Table 15.3) where, at the end of each transmission period, there is a handover of the single channel to the user previously receiving, in order to permit them to reply over the same channel. This is efficient in that it requires only one frequency allocation for the communication link but it has the disadvantage that all units canhear all transmissions provided they are within rage of the mobile and frequencies are allocated for the transmissions. One frequency is used for the forward or downlink, namely base-to-mobile communications. This permits simultaneous two-way communication and greatly reduces the level of interference, but it halves other’s transmissions, which can lead to contention with two mobiles attempting to initiate a call, at the same time, on the uplink in a busy syetem.Although PMR employs relatively simple techniques with analogue speech transmission there have been many enhancements to these systems over the years . Data transmission is now in widespread use in PMR systems using FSK modulation. Data transmission also allows the possibility of hard copy graphics output and it gives direct access to computer services such as databases, etc. Data prembles can also be used, in a selective calling mode, when initiating a transmission to address a special receiver and thus obtain more privacy within the system.15.4.5 Trunked radio for paramilitary use集群无线电的军事使用Another related TDMA mobile radio standard is the European trunked radio(TETRA)network which has been developed as part of the public safety radio communications service(PSRCS) for use by police, utilities, customs office, etc. TETRA in fact is part of wider international collaborations for paramilitary radio use.In these portable radios there is a need for frequency hopping (FH) to give an antieavesdropping capability and encryption for security of transmission to extend military mobile radio capabilities to paramilitary use, i.e. for police, customs and excise offices, etc. these capabilities are included in the multiband interteam radio for the associated public safety communications office in the USA while Europe has adopted the TETRA standard.TETRA is essentially the digital TDMA replacement of the analogue PMR systems. The TETRA standard has spectrum allocations of 380 to 400 and 410 to 430MHz, with the lower band used for mobile transmissions and the upper band for base station use. TETRA mobile have 1 W output power and the base stations 25 W using error with the data throughput rate varying, to meet the required quality of service. TETRA can accommodate up to four users each with a basic speech or data rate of 7.2kbit/s. with coding and signaling overheads, the final transmission rate for the four-user slot is 36 kbit/s. this equipment is large and more sophisticated than a commercial cell phone, and it sells for a very much higher price becase the production runs are much small. However, its advanced capabilities are essential for achieving paramilitary communications which are secure from eavesdropping.15.5 Code division multiple accessAnalogue communication systems predominantly adopt frequency division multiple access (FDMA), where each subscriber is allocated a narrow frequency slot within the available channel. The alternative TDMA(GSM) technique allocates the entire channel bandwidth to a subscriber but constrains the subscriber but constrains the subscriber to transmit only regular short bursts of wideband signal. Both these accessing techniques are well established for long haulterrestrial, satellite and mobile communications as they offer very good utilization of the available bandwidth.15.5.1The inflexibility of these coordinated accessing techniques has resulted in the development of new systems based on the uncoordinated spread spectrum concept. In these systems the bits of slow speed data traffic from each subscriber are deliberately multiplied by a high chip rate spreading code, forcing the low rate (narrowband data signal) to fill a wide channel bandwidth.15.7.2 3G systemsThe evolution of the third generation (3G)system began when the ITU produce the initial recommendations for a new universal mobile telecommunications system(UMTS)[www.] The 3G mobile radio service provides higher data rate services ,with a maximum data rate in excess of 2Mbit/s, but the achievable bit rate is linked to mobility. Multimedia applications encompass services such as voice, audio/video, graphics, data, Internet access and e-mail. These packet and circuit switched services have to be supported by the radio interface and the network subsystem.Several radio transmission technologies(RTT) were evaluated by the ITU and adopted into the new standard, IMT-2000. the European standardization body for 3G, the ETSI Special Mobile Group, agreed on a radio access scheme for 3G UMTS universal terrestrial radio access(UTRA) as an evolution of GSM. UTRA consists of two modes : frequency division duplex(FDD) where the uplink and downlink are transmitted on different frequencies; and time division duplex(TDD) where the uplink and downlink are time multiplexed onto the same carrier frequency. The agreement assigned the unpaired bands (i.e. for UTRA TDD ). TD-CDMA is a pure CDMA based system. Both modes of UTRA have been harmonised with respect to basic system parameters such as carrier spacing, chip rate and frame length to ensure the interworking of UTRA with GSM.The 3G proposal were predominantly based wideband CDMA(WCDMA) and a mix of FDD and TDD access techniques. WCDMA is favoured for 3G in poor propagation environments with a mix of high modest speed data traffic. It is generally accepted that CDMA is the preferred accesstechnique and, with the increase in the data rate, then the spreading modulation needs to increase to wideband transmission.WCDMA is based on 3.84Mchip/s spreading codes with spreading ratio, i.e. , K values, of 4-256 giving corresponging data ratas of 960-15 kbit/s. the upper FDD uplink band I from 1920-1980 MHz is paired with a 2110-2170 MHz downlink. In addition uplink bands II & III at 1850-1910 MHz and 1710-1785 MHz are also paired, respectively, with 1930-1990 MHz and 1805-1880 MHz allocations. the system is configured on a 10 ms frame with 15 individual slots to facilitate TDD as well as FDD transmissions. TDD is more flexible as time-slots can be dynamically reassigned to uplink and downlink functions, as required for asymmetric transfer of large files or video on demand traffic. 3G WCDMA systems use an adaptive multirate speech coder with encoded rates of 4.75-12.2 kbit/s. receivers commonly use the easily integrated direct conversion design, in place of the superheterodyne design . receiver sensitivities are typically -155dBm.The 3GPP2 standard aims to achieve a wide area mobile wireless packet switched capability with CDMA2000 1×EV DO revision A (sometimes called IS-856A). Here 1×refers to the single carrier 1.25 Mchip/s system. It achieves a 3.1 Mbit/s downlink and a delay sensitive services. The 3GPP standard has gone through many release with R4 in 2001 which introduced packet data services and R6 in 2005 to further increase the available data transmission rate . R6 pioneers the use of high-speed downlink packet access and multimedia broadcast multicast services which offer reduced delays and increased uplink data rates approaching 6 Mbit/s.In parallel with the European activities extensive work on 3G mobile radio was also performed in Japan. The Japanese standardisation body also chose WCDMA, so that the Japanese and European proposals for the FDD mode were already aligned closely. Very similar concepts have also been adopted by the North American standardization body.In order to work towards a global 3G mobile radio standard, the third generation partnership project(3GPP), consisting of members of the standardization bodies in Europe, the USA, Japan, Korea and China, was formed. It has merged the already well harmonized proposals of the regional standardization bodies to work on a common 3G international mobile radio standard, still called UTRA. The 3GPP Project 2(3GPP2), on the other hand, works towards a 3G mobile radio standard based on cdmaOne/IS-95 evolution, originally called CDMA2000.比起相对稳定、适度的技术发展是发生在宽带微波通信系统,有长期快速发展和扩大部署的新的移动个人通讯系统。
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科技英语文章翻译任何作品均有特定的文体，原文的文体不同，翻译方法也随之而异。
试观察下列几个片断的原文及其译文。
"It appears that you've got the offer of a very good job.""A wonderful job.""Are you going to take it ?""I don't think so.""Why not?'"I don't want to."“听说有个很好的工作要你去干。
”“挺好的工作。
”“打算干吗？”“不。
”“为什么不干？”“不想干。
”这是小说中的一段对说，属于口语文体。
其特点是：用词自由，句法结构简单，短句与省略句多，自然朴素，生活气息浓厚。
在译文中进一步体现汉语口语的特点，省去主语“你”、“我”；将英语的一个句子I don't think so。
干脆译成一个字“不”，显得简洁有力。
She was of a helpless, fleshy build, with a frank, open countenance and an innocent, diffident manner. Her eyes were large and patient, and in them dwelt such a shadow of distress as only those who have looked sympathetically into the countenances of the distraught and helpless poor know anything about.那妇人生着一副绵软多肉的体格，一张坦率开诚的面容，一种天真羞怯的神气。
一双大落落的柔顺眼睛，里边隐藏着无穷的心事，只有那些对于凄惶无告的穷苦人面目作过同情观察的人才看得出来。
上面五十一个词的片断，就运用了十个形容词，占五分之一。
and in then dwelt such a shadow of distress是非常优美生动的文学语言，译文保持了一风格。
Johns accomplished a spectacular debut for his NHL career tonight, the first score launching a four -point first period out burst,to lead the Johnson City High Hats to a 6:4 victory over the Montreal Teals and their eighth consecutive game without a loss.在全国手球联赛中克拉克约翰斯今晚初试锋芒，引起轰动。
上半场领先四分，首开记录。
克拉克发挥中坚作用，约翰逊市高帽队终以6:4击败蒙特利尔市小鸭队，创造了连胜八场未负一场的战绩。
这是属于应用文的新闻文体，其特点是简明扼要，短小精悍，结构紧凑，笔锋犀利。
上述这则电讯只有一个句子，却把一场球赛描绘得淋漓尽致，富于吸引力。
The range of a voltmeter may be extended by means of a series resistor called a multiplier as shown in Fig.2.The fullscale reading of the meter alone may be 15volts.With the multiplier 250volts may be required to move the pointer to full-scale, 135 volts across the multiplier and 15volts across the meter.从上述的一段科技文章，不难看出其文体与修辞手段与前面列举的文艺小说，新闻报道等迥然不同。
科技文体崇尚严谨周密，概念准确，逻辑性强，行文简练，重点突出，句式严整，少有变化，常用前置性陈述，即在句中将主要信息尽量前置，通过主语传递主要信息。
科技文章文体的特点是：清晰、准确、精练、严密。
那末，科技文章的语言结构特色在翻译过程中如何处理，这是进行英汉科技翻译时需要探讨的问题。
现分述如下：一、大量使用名词化结构《当代英语语法》（A Grammar of Contemporary）在论述科技英语时提出，大量使用名词化结构（Nominalization）是科技英语的特点之一。
因为科技文体要求行文简洁、表达客观、内容确切、信息量大、强调存在的事实。
而非某一行为。
Archimeds first discovered the principle of displacement of water by solid bodies.阿基米德最先发展固体排水的原理。
句中of displacement of water by solid bodies 系名词化结构，一方面简化了同位语从句，另一方强调displacement 这一事实。
The rotation of the earth on its own axis causes the change from day to night.地球绕轴自转，引起昼夜的变化。
名词化结构the rotation of the earth on its own axis 使复合句简化成简单句，而且使表达的概念更加确切严密。
If you use firebricks round the walls of the boiler, the heat loss. Can be considerably reduced.炉壁采用耐火砖可大大降低热耗。
科技英语所表述的是客观规律，因之要尽量避免使用第一、二人称；此外，要使主要的信息置于句首。
Television is the transmission and reception of images of moving objects by radio waves.电视通过无线电波发射和接受活动物体的图象。
名词化结构the transmission and reception of images of moving objects by radio waves 强调客观事实，而"谓语动词则着重其发射和接受的能力。
二、广泛使用被动语句根据英国利兹大学John Swales 的统计，科技英语中的谓语至少三分之一是被动态。
这是因为科技文章侧重叙事推理，强调客观准确。
第一、二人称使用过多，会造成主观臆断的印象。
因此尽量使用第三人称叙述，采用被动语态，例如：Attention must be paid to the working temperature of the machine.应当注意机器的工作温度。
而很少说：You must pay attention to the working temperature of the machine .你们必须注意机器的工作温度。
此外，如前所述，科技文章将主要信息前置，放在主语部份。
这也是广泛使用被动态的主要原因。
试观察并比较下列两段短文的主语。
We can store electrical energy in two metal plates separated by an insulating medium. We call such a device a capacitor, or a condenser, andits ability to store electrical energy capacitance .It is measured in farads.电能可储存在由一绝缘介质隔开的两块金属极板内。
这样的装置称之为电容器，其储存电能的能力称为电容。
电容的测量单位是法拉。
这一段短文中各句的主语分别为：Electrical energySuch a deviceIts ability to store electrical energyIt (Capacitance )它们都包含了较多的信息，并且处于句首的位置，非常醒目。
四个主语完全不同，避免了单调重复，前后连贯，自然流畅。
足见被动结构可收简洁客观之效。
三、非限定动词。
如前所述，科技文章要求行文简练，结构紧凑，为此，往往使用分词短语代替定语从句或状语从句；使用分词独立结构代替状语从句或并列分句；使用不定式短语代替各种从句；介词十动名词短语代替定语从句或状语从句。
这样可缩短句子，又比较醒目。
试比较下列各组句子。
A direct current is a current flowing always in the same direction.直流电是一种总是沿同一方向流动的电流。
Radiating from the earth, heat causes air currents to rise.热量由地球辐射出来时，使得气流上升。
A body can more uniformly and in a straight line,there being no cause to change that motion.如果没有改变物体运动的原因，那么物体将作匀速直线运动。
Vibrating objects produce sound waves ,each vibration producing one sound wave.振动着的物体产生声波，每一次振动产生一个声波。
In communications, the problem of electronics is how to convey information from one place to another.在通讯系统中，电子学要解决的问题是如何把信息从一个地方传递到另一个地方。
Materials to be used for structural purposes are chosen so as to behave elastically in the environmental conditions.结构材料的选择应使其在外界条件中保持其弹性。
There are different ways of changing energy from one form into another.将能量从一种形式转变成另一种形式有各种不同的方法。
In making the radio waves correspond to each sound in turn ,messages are carried from a broadcasting station to a receiving set.使无线电波依次对每一个声音作出相应变化时，信息就由广播电台传递到接收机。