一、句法特点1、长句多Many man-made substances are replacing certain natural materials because either the quantity of the natural product cannot meet our ever-increasing requirement, or, more often, because the physical properties of the synthetic substance, which is the common name for man-made materials, have been chosen, and even emphasized, so that it would be of the greatest use in the field in which it is to be applied.2、大量使用被动语态As oil is found deep in the ground,its presence cannot be determined by a study of the surface,Consequently,a geological survey of the underground rock structure must be carried out. If it is thought that the rocks in a certain area contain oil,a "drilling rig" is assembled．The most obvious part of a drilling rig is called a "derrick". It is used to lift sections of pipe,which are lowered into the hole made by the drill. As the hole is being drilled,a steel pipe is pushed down to prevent the sides from falling in.If oil is struck a cover is firmly fixed to the top of the pipe and the oil is allowed to escape through a series of valves.3、形容词短语作后置定语All radiant energy has wave like characteristics，analogous to those of waves that move through water.Non-mobile robots，capable of learning to perform an industrial task and then of being left to perform it tirelessly，are now in use in industrialplants all over the world.4、非谓语动词使用频率高Today the electronic computer is widely used in solving mathematical problems, having to do with weather forecasting and putting satellites into orbit.Numerical control machines are most useful when quantities of products to be produced are low or medium；the tape containing the information required to produce the part can be stored，reused or modified when required.二、语法特点（汉译英）1、在科技英语中往往采用客观的叙述,所以表示将来时用will,而很少用be going to表示将来The new aircraft will fly for the first time on Monday.2、表示纯粹未来用will，如:明年开始生产这种新机器.Production of the new machine will commence next year.表示能力用will,can,capable和be able to。
如:这几架飞机的飞行速度可达每小时800英里.These planes (will,are able to,can ) fly at 800 miles per hour.表示经常发生的事用will。
如:当我们给它加热时这种固体会汽化.This solid will vaporize when we heat it．表示有时发生的事用may, can。
如:金属迅速冷却会产生裂缝。
Metal which cools rapidly (may or can) cause fracture.表示能够用can。
如:我们可以很容易地算出热量损耗.We can easily calculate the heat losses.表示可能性用can,may。
如:丙酮(可用)水进行吸收。
Acetone (maybe or can be) absorped in water.3、可用should表示告诫。
如:这些机器应当小心操作.These machines should be handled with (great）care.如:任何时候都应注意安全措施.Safety precautions should be observed at all times.可用should说明某一情况如:Carbon content in steel should not be more than 0.5％．如:The maximum internal diameter should be 4 tenths of an inch.最大内径应为4/10英寸.可用should表示期待如:This building should be completed by the end of next year.4、在科技翻译中,如果动作主体是人的时候,在句末通常不用by短语,因为这种短语是多余的. 如:可用多种方法产生热.Heat can be generated in several ways by us.其中的by us就是多余的.但是动作主体不是人时,就应当在英译中加上by短语.如:现代工业需要大量的蒸汽.Large quantities of steam are required by modern industry.如:没有足够的水就无法发展农业.Agriculture cannot be developed without sufficient water．如:爆炸是由燃料与空气中的氧迅速化合而引起的.Explosion is caused by the rapid combination of the fuels with the oxygen in the air.如:设计者应当承担事故的一切责任.All responsibility for the accident must be accepted by the designers.5、科技英语中常用名词+名词的结构,在此结构中前面的词相当于后面名词的定语,用来表示多种不同的关系.表示原材料：如:石油产品oil products=products made from oil表示典型成分：如:锰钢manganese steel=steel which contains manganese表示工作介质：如:蒸汽机a steam engine =an engine worked by steam表示工作对象如:空压机an air compressor=a device for compressing air表示用途如:汽车发动机an automobile engine=an engine for an automobile表示方式如:脚踏制动器a foot brake=a brake operated by foot表示所属：如:水分子water molecules＝molecules of water表示关于如:生产费用the production cost=the cost concerning production表示形状如:星形轮a star wheel=a wheel shaped like a star当名词前面有两个以上的名词作其修饰语时，各个名词之间可能存在各种多级修饰关系. 如:卫星通讯技术satellite communication techniques6、一般不用's表示所有关系，一般是用名词+of+名词的结构来表示所有.如地心引力译为：gravitational pull of the earth，很少译为：the earth's gravitational pull。
月球的表面译为：the surface of the moon，很少译为：the moon's surface。
三、词类转换1、名词的转译Total determinationof molecular structure is possible by means of X-ray diffraction.用X射线衍射法可全面地确定分子结构.(n.→v.)The maiden voyage of the newly-built steamship was a success.那艘新造蒸汽船的首航是成功的.(n.→adj.)2、动词的转译Many chemical reaction need heat to make them take place.许多化学反应的发生都需要热.(v.→n.)The methyl group on the benzene ring greatly facilitates the nitration of toluene. 苯环上的甲基使甲苯非常易于硝化.(v.→adv.)3、形容词的转译There is a large amount of energy wasted owing to friction.由于摩擦而消耗了大量能量.(adj.→v.)General speaking, methane series are rather inert.总的来说,甲烷系的烃惰性很强.(adj.→n.)4、副词的转译The chemical experiment is over. 化学实验结束了.(adv.→v.)The image must be dimensionally correct. 图的尺寸必须正确.(adv.→n.)The film is uniformly thin. 该膜薄而均匀.(adv.→adj.)四、句子成分的转换1、主语的转译Evaporation emphasis is placed in concentrating a solution rather than forming and building crystals.蒸发着重于将溶液浓缩,而不是生成和析出晶体. (主语→谓语)Organic compounds are not soluble in water because there is no tendency for water to separate their molecules in ions.有机化合物不溶于水,因为水没有将它们的分子分成离子的倾向. (主语→宾语) Methane is less than half as heavy as water.甲烷的重量不到水的一半. (主语→定语)When a copper plate is put into the sulfuric acid electrolyte, very few of its atoms dissolve.当将铜极片置于硫酸电解液中,几乎没有铜原子溶解. (主语→状语)2、谓语的转译The past few decades have been characterized by a prodigious expansion of the organic-chemical industry.过去数十年的特征是有机化学工业得到了惊人的发展. (谓语→主语)The melting point of alkanes are rather irregular at first, but tend to rise somewhat steadily as the molecules become large.烷烃的熔点起初很不规则, 但随着分子的增大, 则有些稳步上升的趋势. (谓语→宾语)3、宾语的转译TNT has high explosive power. TNT的爆炸力很大. (宾语→主语)Light makes vision possible. 有了光才能看见东西(宾语→谓语)4、表语的转译Matter is anything that occupies space. 凡占有空间的都是物质. (表语→主语)In this sense structure analysis is common to most organic research.从这个意义上讲结构分析普遍应用于大多数的有机研究. (表语→谓语)5、定语的转译There are two groups of metals: pure metals and their alloys.金属有两大类:纯金属及其合金. (定语→主语)Many factors enter into equipment reliability.涉及设备可靠性的因素很多. (定语→谓语)Benzene can undergo the typical substitution reactions of halogenation, nitration, sulphonation and Friedel-Crafts reaction.苯可进行典型的取代反应, 如卤化.硝化.磺化和傅氏反应. (定语→同位语)6、状语的转译When oxides of nitrogen are absorbed in water to give nitric acid, a chemical reaction occurs.当水吸收氮氧化物形成硝酸时, 就发生了化学反应. (状语→主语)TNT is simple and relatively safe to manufacture.制造TNT简单而且比较安全. (状语→谓语)In the simplest chemical cell the electrolyte is solution of sulfuric acid in water. 在最简单的化学电池内, 电解液是硫酸的水溶液. (状语→定语)The attractive force between the molecules is negligibly small.分子间的吸引力小得可以忽略不计. (状语→定语)五、被动语态的译法1、仍译成被动语态The atomic theory was not accepted until the last century.原子学说直到上个世纪才为人们所接受.The laws of thermodynamics will be discussed in the next articles.热力学定律将在下文予以讨论.2、译成汉语主动句Measures have been taken to diminish friction.已经采取了一些措施来减少摩擦.If the product is a new compound, the structure must be proved independently. 如果产物是一个新化合物，则必须单独证明其结构.加译人们.我们.有人.大家等主语The metal, iron in particular,is known to be an important material in engineering. 大家知道,金属,特别是铁,是工程方面的重要原料.If one or more electrons are removed, the atom is said to be positively charged. 如果原子失去一个或多个电子,我们就说这个原子带正电荷.3、用英语中的动作者做译文中的主语The molecules are held together by attractive forces.引力把分子聚集在一起.4、将英语中的一个适当成分译作译文中的主语The oxides of nitrogen are absorbed in water to give nitric acid.水吸收氮氧化物形成硝酸.5、在原主语前加译把.将.使.给等词Absorption process is therefore conveniently divided into two groups: physical process and chemical process.因此,可将吸收过程简单地分为两类:物理过程和化学过程.6、将被动语态译成是…的.对…进行等The slurry is filtered to recover the electrolyte solution.对泥浆进行过滤可回收电解液.An aldehyde is prepared from the dehydrogenation of an alcohol and hence the name. 醛是从醇脱氢而制备的,并因此而得名.7、被动意义译成主动意思Batch operations are frequently found in experimental and pilot-plant operations. 间歇操作常见于实验室操作及中试操作.In the reaction both the acid and the base are neutralized forming water and salt. 反应中,酸与碱彼此中而形成水和盐.六、后置定语的译法1、介词短语作后置定语The presence of a substituent groupin benzene exerts a profound control over both orientation and the ease of introduction of the entering substituent.苯中取代基的存在对进入基团的方位及进入的难易程度都起着强有力的控制作用。