1、1,科技英语语法特点,2,1 Grammar Features,客观性（Objective）、准确性（accuracy）和精练性(conciseness)。,(1) 广泛使用被动语态,(2) 广泛使用非谓语形式,(3) 省略句使用频繁,(4) It句型和祈使句使用频繁,(5) 复杂长句使用频繁,(6) 后置形容词短语作定语多,语法特点,（7）过去分词和现在分短语作后置定语,(8) 科技英语中常用虚拟语气,3,(1) 广泛使用被动语态,主体多为客观的事物、现象和过程，在叙述推理过程中切忌加进作者个人的主观臆断；,中心是客观现象及事物本身，而非动作的发出者，把论证说明的对象置于句子主语的位置，既能
2、突出中心，又能吸引读者的注意。,(客观性),1) Electricity can be measured in amount and quality.,电可以用数量和质量来度量。,2)Instrument transformers are installed on the high-voltage equipment.,互感器安装在高压设备上,4,3) The author has also described the purification of chemicals in this paper.（作者在论文中还描述了化学药 品的提纯）主动语态。4) The purification of
3、chemicals has also been described in this paper（本文还描述了化学药品的提纯）被动语态。,5,当需要着重强调动词及其动词对象之间的关系或者行为发生者没有必要说明 往往用被动语态，因为很多被动句中没有行为的发出者，也就不必使用by短语了，例如，在描述实验步骤时往往用被动语态：,5) In an inert atmosphere box, a 160ml stainless steel vessel was charged with a stirring bar, the catalyst (0.3g) and 10ml furfural. The v
4、essel was then sealed, removed from the box and flushed with H2 and finally pressurized to 3MPa H2. The vessel was placed into a oil bath, heated with constant vigorous magnetic stirring to 140and allowed to remain here to react for 5 hours. The products were examined using a SP-501GC.,6,在被动语气句中，by短
5、语有时用来表示方法或手段，而不是行为的发出者，例如。6) The temperature of the liquid was raised to 100 by heating.加热使液体的温度上升到100。Magnetic measurements were performed (by) using Faraday method. 用法拉第法进行磁测定。by可省略。Useful data may be collected by doing experiment 通过实验可以收集到有用的数据。,7,9) Electric power is generated in power generatin
6、g stations or plants.,电能是在发电站或发电厂产生的,10) The meters are calibrated and the scale is designed to read the value of the desired unit.,这些仪表可以被校准并且设计了不同的量程 ，以便读出期望的数值。,11) Electrical energy can be stored in two metal plates separated by an insulation medium. Such a device is called a capacitor, and its
7、ability to store electrical energy is termed capacitance. It is measured in Farads.,电能可以储存在被一绝缘介质隔开的两块金属板中，这样的装置被称为电容器，它储存电能的能力就被称为电容。电容的测量单位是法拉。,8,(2)广泛使用非谓语形式,非谓语动词在句子中可以起到名词，形容词或副词作用，动词的非谓语形式分为动名词,分词,动词不定式。, 动名词,用动名词短语取代时间从句或简化时间陈述句,The signal should be filtered before it is amplified.,2) An obje
8、ct becomes hot. It is placed in the sun.,Once being placed in the sun, an object becomes hot.,物体放置在太阳下会变热。,The signal should be filtered before being amplified.,放大信号前，应先对其进行滤波,(精炼),9,3) We must do various experiments before a new electronic product is designed.,Before designing a new electronic prod
9、uct we must do various experiments.,在设计一个新的电子产品之前，我们必须做各种实验,用动名词短语做主语,4) Changing resistance is a method for controlling the flow of the current.,改变电阻是控制电流的一种方法,5) Conducting electricity means the flow of electrons through an object.,传导电流意味着电子在物体内的流动,10, 分词,过去分词短语替代从句中的被动语态 现在分词短语替代从句中的主动语态,The powe
10、r supply, which is shown in block-diagram in Fig.1, is a single-phase switch-mode inverter.,The power supply shown in block-diagram in Fig.1 is a single-phase switch-mode inverter.,图1中用框图表示的电源是一个单相开关逆变器。,11,2) A three-phase circuit, as it was pointed out above, is merely a combination of three singl
11、e-phase circuits.,A three-phase circuit, as pointed out above, is merely a combination of three single-phase circuits.,正如上面所指出的那样，三相电路只不过是三个单相电路的组合。,3) The transistor, which is working with correctly polarities, can work as an amplifier.,The transistor working with correctly polarities can work as a
12、n amplifier.,工作于正确电源极性下的晶体管，作用就像放大器。,12, 不定式,用不定式短语来替代表示目的和功能的从句或语句,(1) The capacity of individual generators is larger and larger so that the increasing demand of electric power is satisfied.,The capacity of individual generators is larger and larger to satisfy the increasing demand of electric pow
13、er.,单台发电机的容量越来越大，目的就是满足不断增长的用电需求。,(2) What does a fuse do? It protects a circuit.,The function of a fuse is to protect a circuit.,保险丝的作用就是保护电路。,13,(3) 省略句使用频繁,省略成分：状语从句中的主语、全部或部分谓语；定语从句中的关系代词which和that、从句中的助词等；还常用介词短语替代从句。,1) If it is possible, the open-loop control approach should be used in this s
14、ystem.,If possible, the open-loop control approach should be used in this system.,2) As illustrated in Fig.1, there is a feedback element in the closed-loop system.,As in Fig.1, there is a feedback element in the closed-loop system.,就像图1所示的那样，这个闭环系统中有一个反馈元件。,可能的话，这个系统应该使用开环控制方法。,(精炼),14,3) The devic
15、e includes an instrument transformation and a relay system which has two circuits in it.,The device includes an instrument transformation and a relay system with two circuits in it.,这个装置包括一个互感器和一个有两个电路的继电器系统。,As already discussed 前已讨论As explained before 前已解释As described above 如上所示If possible (necess
16、ary)如果可能（必要）,其他常用的省略形式：,If so 倘若如此As previously mentioned 前已提到When needed (necessary, feasible)必要时Where feasible 在实际可行的场合Where possible 在可能的情况下,15,(4) It句型和祈使句使用频繁,It句型：it 充当形式主语，避免句子“头重脚轻”,It is very important (possible, necessary, natural, inevitable) to,It takes very much time learning,It is clea
17、r (possible, necessary, natural, inevitable) that,It happened that ,It must be admitted that,祈使句: 无主语，精炼。,Let A be equal to B.设A等于B。,Consider a high-pressure chamber. 假如有一个高气压气候室。,（准确、精炼）,16,(5) 复杂长句使用频繁,1) It has been mentioned above that the electrons in a metal are able to move freely through the
18、 metal, that their motion constitutes an electric current in the metal and that they play an important part in conduction of heat.,前面已经提到：金属中电子能自由地通过金属，电子的移动在金属中形成了电流，电子在热传导中起着重要的作用。,（准确、精炼）,科技英语中经常使用修饰成分比较多的简单句或复合句，句子一般较长，多为完整句。句子的逻辑关系比较明确，时态较简单，少用省略句，甚至关系代词which , that等都不简略，绝大多数科技期刊出版机构都要求用完整句子来描述
19、内容。,17,2) We learn that sodium or any of its compounds produces a spectrum having a bright yellow double line by noticing that there is no such line in the spectrum of light when sodium is not present. But that if the smallest quantity of sodium be thrown into the flame or other sources of light, th
20、e bright yellow line instantly appears. By noticing是状语，修饰learn, noticing有两句从句作宾语。,18,由前面两例可见：1.科技英语句子包括的信息量大，一环扣一环，非常严谨，因而可以反映出客观事物的复杂关系，若分成若干短句，就不一定那么严谨了。2.句子结构虽复杂，句子各部分之间的逻辑关系却很清楚，时态简单，少用省略句。 科技英语中句子一般为完整句，但科技书刊、论文等题目则一般避免使用句子，不要用介词短语和不定式动词短语，常用词类有名词、名词词组或名词短语，有些地方可以省略冠词，如书名principles and applicat
21、ions of organotransition metal chemisty.（有机过渡金属化学的原理和应用）。论文和书名在必要时可以加副标题, 如Telecommunication system Engineering 副标题 Analog and Digital Network Design电信系统工程模拟和数字网的设计。,19,3) The reluctance motor operates synchronously at a speed which is determined by the supply frequency and the number of poles for w
22、hich the stator is wound.,磁阻电动机以某一速率同步动转，该速率是由电源频率和定子绕制的级数决定的。,4) The testing of a cross-field generator will be described in this section with chief reference to the tests that are normally taken on every machine before it leaves the makers works.,交磁发电机的试验将在本节中叙述，它主要涉及每台电机在离开制造厂前应进行的试验。,20,(6) 后置形容
23、词短语作定语多,代替定语从句作后置定语，使句子简洁、紧凑，不至于累赘。,1) All radiant energies have wavelike characteristics, which are analogous to those of waves moving through water.,All radiant energies have wavelike characteristics analogous to those of waves moving through water.,2) The instruments present include some digital
24、ones which are relative to DSPs,The instruments present include some digital ones relative to DSPs,所有的辐射能都具有波的特性，与水中移动的波的特征相似。,到场的仪器中还有一些与DSP有关的数字仪器,（精炼）,21,3）How can we obtain ethanol free of water （怎样才能得到无水乙醇呢），这里free（形容词）+of（介词）作 ethanol的后置定语。4）A machine is composed of rigid bodies having definit
25、e motions and capable of performing useful work 机械是由一些具有一定运动并能做有用功的刚体组成的，capable of 是后置定语修饰bodies.5）Any subject floating on or submerged in a liquid is buoyed up by a force equal to the weight of the displaced liquid. Equal to是后置定语修饰force.,22,Without forces sufficient to overcome the resistance, bod
26、ies at rest never move. （没有足够的力克服阻力，静止物体永久不会移动。） 形容词sufficient带有不定式短语to overcome the resistance修饰名词forces，因而后置。,6) 当形容词带有不定式修饰名词时，后置,23,In our Lab the only instrument available is X-ray fluorescence spectrometer. 我们实验室唯一可用的仪器是X射线萤光分光计。这里available=that is available 作instrument的定语.,7) 形容词作定语具有表语性质时，后置
27、,24,8) some, any, every, no同body, one, thing构成复合代词，形容词后置,Is there anything new in this book? （本书有什么新内容吗？） new为形容词，与anything连用，故后置。There is nothing special in this paper. 这篇论文中没有什么特殊内容。 special作nothing的后置定语。Everybody present was deeply moved. 出席的每个人都深受感动。 present修饰everybody.,25,（7）过去分词和现在分短语作后置定语,1)
28、The test methods used in this report were state-of-theart techniques for measuring particle-collection efficiencies本 报道使用的测定方法测粒子收集效率具有当今先进工艺水 平的技术。 Used in this report作methods的后置定语。2) Monatomic cations having single oxidation numbers take the name of the metal from which they are derived. For examp
29、le, Na+ is named sodium.,26,(8) 科技英语中常用虚拟语气,科技书刊中很多内容是有关科学家对事物或现象的论证推测和探讨，经常涉及各种条件，所以在不少场合有必要使用虚拟语气。,27,1) 虚拟语气时态,A. 现在时 用来表示现在或将来可能实现的设想， 从句中的谓语动词一律用原形表示。例如 If the temperature of the gas be increased, the gas will tend to expand. （如果气体温度升高，它就要膨胀。）,28,B. 过去时 用来表示与现在事实相反的假设，从句中的谓语 用过去时，be的多种形式全用were，
30、主语的谓 语用should, would, could, might +动词原形。 If metals had no such properties as ductility and malleability, machines could not be made. （假如金属没有延性、展性这些特性，就不能制 造机器）。,29,C. 过去将来时 用来表示和将来事实相反的假设，从句中 谓语用should, could, might +动词原 形，或were +不定式，主句中的谓语用 should, would, could或might +动词原形。 例如：If he were to do thi
31、s test, he might do it in some other way. (要是他做这次实验，可能用另外某种方法去 做。),30,D. 过去完成时 用来表示和过去事实相反的假设，从句 中谓语用过去完成时，主句中的谓语中 should, could+have过去分词，例： If more water had been used, the temperature change would have been smaller （如果多用点水，温度变化就会少一些。）,31,2) 虚拟语气的用处,A. 科学家在表示对各种问题看法时，为了口吻委婉，往往采用虚拟语气，比如陈述自己的看法。例：The
32、 situation could still be remedied, I suppose.（我看这种情况也许也有补救的余地）I should think the approach is correct. （我想这种处理方法是对的。）,32,B. 表主委婉的请求，建议，劝告例：Would you turn off the light？ （请你把灯关掉好吗？）It wouldnt be a bad idea for us to solve the problem in another way.（我们换一种方法解决这个题倒不错。）These chemicals should have been k
33、ept in some dry place.那些化学药品理应保存在干燥的地方。,33,C. 从句中使用虚拟语气表示要求，劝告，建议，希望， 命令等。 主语从句：在以引导词it为形式主语的句子里，其从 句的虚拟语气是：谓语用(should)+原形动词，例如： It was suggested that such devices should be designed and produced without delay. （有人提议立即设计和生产这种装置。） 同样，Its necessary that, It is required that, It is important that, It i
34、s recommended that, It is desired that后面都可用虚拟语气。,34,(2) 宾语从句：在suggest, order, demand, desire, propose, insist等动词后的英语从句用虚拟语气，例 如：The doctor suggested that he (should) have a three days rest.（医生建议他休息三天。）(3) 表语从句: 用于suggestion, order, plan, idea等名词 后面表语从句，或同位语从句，例如： His supervisor made a suggestion tha
35、t he (should) finish his experiments before National Day. 他导师建议他在国庆节完成他的实验。,35,虚拟语气有时不用条件从句，句子本身就暗示了虚拟条件或用介词短语表示条件，例如：Gas molecules move in all directions, otherwise the color could not spread throughout the bottle.气体分子是到处运动的，不然的话，颜色就不可能扩散致整个瓶子。再如：Without water the earth would undergo extreme change
36、s in temperature.Without you, I would die.,36,2. Rhetoric Features,注重科学技术方面的观察、试验和客观规律、事物特征,涉及的内容(如概念、原理、定理或定律、规则、方法等)大多没有特定的时间关系和时效性,(1) 广泛使用一般现在时,(2)较多地使用图、表和公式,常使用数据、图、表和公式等非语言因素来表明科技概念、原理、定理或定律、规则、方法等。,(3) 逻辑语法使用多,修辞特点,进行条件论述、理论分析和公式推导时，多使用逻辑语法，即表示条件、原因、语气转折、限制、假设和逻辑顺序等词汇,although, because, but,
37、 if, once, only, suppose, as a result, because of, due to, so, therefore, thus, without等。,37,3. Vocabulary Features,(1) 词汇分类,专业或技术词汇,次技术词汇,diode ， capacitor ，substation , autotransformer ，superconductivity 。,很多专业和学科所共有的词汇,不同专业和学科往往具有不同词义,某个专业所特有的词汇，其专业性强，词义狭窄和单一。,power :,幂，乘方,动力，功率，效率,电源，电力，功率，电能,bu
38、s:,公共汽车,母线,总线,Condenser：,电容器，补偿机,冷凝器,power plant:,发电厂,动力装置,：专业或技术词汇，次技术词汇，非技术词汇,(二极管),（电容器）,(变电站，变电所),（自耦变压器）,(超导特性),38,非技术词汇,在普通英语或非专业英语中使用较少，但实际却属于非专业英语的词汇,take in - absorb,Look into - examine,find out - discover,turn round - rotate,make good use of - utilize,change - convert,39,4. 科技文章写作中常见的英语语法问
39、题,有的语法对科技论文写作可能关系不大，如将来式的用法，但同样一些语法对科技论文写作特别重要，清晰的实验描述和准确的思想表达对科技写作尤其重要，宁愿多写一些句子，也要把事情表达清楚，也就是不能为达到简洁而牺牲清晰。句子可以写得简单，用词可以有些单调，但语句的意思一定要清楚。科技写作的语法特点就是为了保证语句的清晰，不同的人对英语语法的掌握程度不同，我根据自己修改论文的经验,介绍一些科技写作中经常遇到的语法问题。,40,1)主语和谓语的单数和复数要一致英语中名词有它的单数和复数形式，动词也有它的单数和复数形式 , 二者要一致 . 单数主语 ( subject) 名词要用动词 (verb) 的单数
40、 (singular) 形式 , 复数主语名词要用动词的复数 (plural) 形式 . 我们写中文的不太习惯英语的这种写法 , 很难做到不假思索地配对 , 需要特别 留心才能不出错误， 特别是当主语名词和动词被分开时 . 试看下面的例句 . A high percentage of peptides that are made of amino acids are present in the sample. A high percentage 才是真正的主语， 而不是邻近的 amino acids , 所以应该用单数形式 . 宜改为 : A high percentage of pepti
41、des that are made of amino acids is present in the sample. 让事情更复杂的是英语名词被分为不同的种类， 其中的一类叫集合名词 . 它既可以当单数用词也可以当复数用 . 集合名词当整体 来讲时是单数，每个成员作为个体时用复数 . The number of mice in the experiment was increased. A number of mice have died. All of the samples were analyzed. All of the safety procedures was strictly f
42、ollowed,41,代词 none 既可以是单数也可以是复数 . 当 none 后面的词是单数时 , 用单数动词 . 当 none 后面的词是复数时， 用复数动词 . None of the information was useful. None of the animals were starved. 描写数量， 重量，体积，时间等的词用单数， 但如果是分次添加或减少时用复数 . 在这个意义上同 集合名词类似 . 1.5 ml was added. 10 g was added . 6 hours was the required incubation time. 5 g were ad
43、ded stepwise. 简写的数量单位， 如 mg, ml, s 等， 单数和复数的写法是一样的 , 如 1mg, 5 mg. 一些词如 series, type, portion, class, 要用单数形式 . A series of derivatives of penicillin was prepared. A large portion of the reports is focused on how to deal with the increased cost. Data, criteria, phenomena, media 是复数形式， 他们的单数形式分别是 datum
44、, criterion, phenomenon, medium.,42,2） 修饰语同主语名词关系上要一致,当用 1 ) 动名词 (gerund) ， 2) 分词短句 (participle) ， 3) 不定式短句 (infinitive) 作修饰语时， 修饰语中的动词要同主句中的主语名词关系 上 要 一致 . 科技杂志论文中有这种语法错误的情况较多 . 严格来讲这只是种语法错误， 一般不影响对句子 的内容的理解， 所以很多作者不 太注意 . 编辑和阅稿人有时也没有严格要求改正 . 比如下面就是 Nature 杂志 2006 年第 439 卷中的一个例子 . Using the enhance
45、r GAL4/UAS expression system, short-term memory traces of aversive and appetitive olfactory conditioning have been assigned to output synapses of subsets of intrinsic neurons of the mushroom bodies. （1) 动名词 After finishing the purification, the activity of the isolated compound was then studied. We
46、or I 是动名词 finishing 形式上的主语， 同主句的主语 activity 不一致 . 宜改为 : After purification was finished, the activity of the isolated compound was then studied. 或 : After finishing the purification, we studied the activity of the isolated compound. Treated with the new drug, the blood cholesterol levels of particip
47、ants were lowered by an average of 30%. 宜改为 : Treated with the new drug, participants showed an average of 30% decrease in their blood cholesterol levels.,43,（2) 分词短句 The iron concentration was determined using the Fenton reaction method. The iron concentration 同 using the Fenton reaction method 关系上
48、不一致 . 宜改为 : The iron concentration was determined by the Fenton reaction method. 或 : We determined the iron concentration using the Fenton reaction method. When measuring the atmospheric level of carbon dioxide, air samples from a remote place, such as an island, is preferred. 宜改为 : When the atmosph
49、eric level of carbon dioxide is measured, air samples from a remote place, such as an island, is preferred. （3) 不定式短句 To further investigate the potential role of biking in causing infertility, an expanded population of biking athletes was surveyed. 不定式短语的形式主语是 we or I ， 同主句主语 population 不一致 . 宜改为 : To further investigate the potential role of biking in causing infertility, we surveyed an expanded population of biking athletes. To confirm the diagnosis, blood test was ordered. 宜改为 : To confirm the diagnosis, the doctor ordered blood test.,
