科技英语1第一章

null科技英语Ⅰ 科技英语Ⅰ 30学时English for Science and Technology本课程的主要 内容 财务内部控制制度的内容财务内部控制制度的内容人员招聘与配置的内容项目成本控制的内容消防安全演练内容 本课程的主要内容科技英语的特点 16学时 科技英语中常用概念的英译 10学时 科技英语中的非谓语动词 4 学时前言前言Preface科技英语的含义 科技英语与其它英语的区别 科技英语的重要性null科技英语的含义 不同于普通英语； 更不同于文学英语； 也不完全等同于专业英语。 English for Science and Technology 专门服务于理工科专业和各行业的科技人员。科技英语与其它英语的区别科技英语与其它英语的区别文学英语：需了解美国文化背景，语言漂亮 普通英语：以语法为主线，基础词汇 科技英语：注重翻译技巧，严谨，忠于原文，但不一定要直译， 如:英文中的被动句←→中文中的主动句。科技英语的重要性科技英语的重要性国际间的科技情报和资料交流； 世界上科技杂志有六万多种，一半以上是英文刊物； 各国科技人员学习的需要； 交流的需要；1 科技英语的特点1 科技英语的特点1.1 科技英语的特点概述 1学时 1.2 科技英语的特殊语法现象 6学时 1.3科技英语中的一些常用句型 4学时1.1 科技英语的 特点概述1.1 科技英语的 特点概述一、科技英语在词汇方面的特点 二、科技英语句法上的特点 三、科技英语修辞上的特点一、科技英语在词汇方面的特点一、科技英语在词汇方面的特点① 专业词汇出现率低； ② 词义专一； ③ 多来源于拉丁语和希腊语； ④ 广泛使用缩略语； ⑤前后缀出现率高缩略语缩略语普通英语中的缩略语：i.e.即，etc.等，co.公司； 科技英语中缩略语多为单位名称、设备名称，仪器， 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 ，药剂等，一般在上下文中有原型。如： 英国电气工程师学会 Institution of Electrical Engineers 简称 IEE 美国科学情报研究所 Institute for Scientific Information 简称 ISI 核磁共振 Nuclear Magnetic Resonance简称 NMR 聚丙烯酰胺 PAM前缀前缀Semi-半，部分的Micro-小，微Thermo- 热Auto- 自，自身Semi-conductor 半导体 Semicircle 半圆Microbiology 微生物学 Microchemistry 微量化学 Microelectronics 微电子学 Microfilm 缩微胶卷Thermodynamic 热力学的 Thermometer 温度计Autobiographic 自传的 Automat 自动售货机 Automation 自动化后缀后缀-ance -ity -ment -ness -sion -tion -th(序)-ure -able -ible -ant -al -ic -ive -ous二、科技英语句法上的特点二、科技英语句法上的特点① 长句多； ② 大量使用被动语态； ③ 常用形容词短语做后置定语； ④ 使用非谓语动词的频率特别高。三、科技英语修辞上的特点三、科技英语修辞上的特点① 时态运用有限； ② 修辞手法简单； ③ 逻辑-语法词使用普遍，如： 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 示原因caused by, as because of, due to owing to, for as a result of, because 表示逻辑顺序however, but nevertheless otherwise表示限制only, if only except besides unlesssuppose supposing assuming provided providing表示假设21.2 科技英语的特殊语法现象1.2 科技英语的特殊语法现象五、关于动作主体的问题 六、命令句的用法 七、by, with的用法 八、关于“名词+名词”的问题 九、很少用“‘s”表示所有 十、定语从句中与which、when连用的介词位置 一、关于be going to 表示未来的问题 二、will, can, may的用法 三、无人称被动句的用法 四、should的用法特殊语法现象特殊语法现象十一、关于if 子句的问题 十二、从句的紧缩式 十三、完成时的用法 十四、as的用法十五、such that, such as to 的用法 十六、关于抽象名词的用法 十七、动词+后缀当形容词 十八、常用的前缀 十九、多用正规动词，少用“动词+副词”一、be going to 表示未来的问题一、be going to 表示未来的问题科技英语中很少用be going to 表示将来。√The new aircraft is going to fly for the first time on Monday.The new aircraft will fly for the first time on Monday.这架新飞机将在礼拜一首次航行。二、will, can, may的用法二、will, can, may的用法The new motorway will have three traffic lanes in each direction。Production of the new machine will commence next year.明年开始生产这种新机器。新高速公路的两侧各有三条相反方向的交通线。表示纯粹未来用will（1）二、will, can, may的用法二、will, can, may的用法These planes will fly at 这几架飞机的飞行速度可达到每小时800英里。表示能力用will, can,capable,和be able to（2） can fly are capable of flying are able to fly800 miles per hour.二、will, can, may的用法二、will, can, may的用法This solid will vaporize when we heat it.Friction will cause the bearings to become heated. 摩擦会使轴承变热。 当我们给它加热时，这种固体会汽化。表示经常发生的事用will（3）will, can, may的用法will, can, may的用法Metal which cools rapidly Unguarded belts or chains The testing of new machinesmay cancause fracture. cause accidents. take a long time.表示有时发生的事用may, can（4）二、will, can, may的用法二、will, can, may的用法We can easily calculate the friction losses.Work on the new engine can start in a few weeks. 几周内可以开始这种新型发动机的工作。 我们可以很容易的算出摩擦损耗。表示能够用can（5）will, can, may的用法will, can, may的用法This problem Low-speed bearings The steel Thermo-couplesmay be can be approached in several ways. lubricated with grease. quenched in either water or oil. used to measure high temperatures.表示可能性用may, can（6）三、无人称被动句的用法三、无人称被动句的用法√The driver starts the engine.The engine is started.（司机）开动发动机。√He welded the plates together.The plates are welded together.把钢板焊接在一起。√The furnace smelts the ore.The ore is smelted in the furnace.高炉熔化矿石。三、无人称被动句的用法三、无人称被动句的用法√The man sharpened his tool.His tool was sharpened.那人磨尖了它的工具。√We must lubricate bearings.Bearings must be lubricated.（我们）必须润滑轴承。√A lathe can cut screws.Screws can be cut on a lathe.车床能加工螺丝。三、无人称被动句的用法三、无人称被动句的用法或Attention should be paid not to damage the machine.（操作者）应当注意不要损坏了机器。The heat in the center of the earth is being made use of in some countries.在某些国家，人们利用地球中心的热。Use is being made of the heat in the center of the earth in some countries.四、should的用法四、should的用法Safety precautions should be obsered at all time.These machines should be handled with great care.这些机器应当小心操作。任何时候都应注意安全措施。表示“告诫”（1）The results of the experiment should be plotted on a graph.应将实验结果绘在图表上。四、should的用法四、should的用法Carbon content in steel should not be more than 0.5%.The steel should not contain more than 0.5% of carbon.钢里的含炭量不应超过0.5%。说明某一情况（2）The maximum internal diameter should be 40 thousandths of an inch.最大内径应为40/1000英寸。或四、should的用法四、should的用法This building should be completed by the end of next year.The process of cooling should continue for several hours.冷却过程要延续好几个小时。这座大楼应在明年年底前竣工。表示“期待”（3）五、关于动作主体的问题五、关于动作主体的问题① 动作主体是人时，句末不用by短语； ② 动作主体不是人时，句末应用by 短语； ③ 动作主体为人，但省去影响句子的意思时，应加by短语。2动作主体动作主体没有足够的水就无法发展农业。Agriculture cannot be developed without sufficient water.Explosion is caused 爆炸石油燃料与空气中的氧迅速化合而引起的。动作主体是人，不用by动作主体不是人，用bycombination of the fuels with the oxygen in the air. by the rapid 动作主体动作主体一个操作者可以同时控制三台机器。Three machines can be controlledAll responsibility for the accident must be accepted 设计者应承担产生事故的一切责任。 by the designer. by a single operator. 强调动作 主体，用by六、命令句的用法六、命令句的用法表示无人称指令Allow Let Take 祈使句 动词开头Should 命令句e.g. Water should be heated before… The bearing should be lubricated before…命令句命令句Let me by! 让我过去！ Let it alone! 别管它！ Let him be! 别打扰他！日 常 英 语将轮胎里的气放掉！科 技 英 语Let the air out of the type！把瓶子里的水倒出来。Let the water out of the bottle.null每十分钟测一次温度！Take the temperature every ten minutes.假设X等于每分钟的转数。Let X equal the number of revolutions per minute.记下水面位置。Take the water level.让水冷却十分钟，然后再测温度。Allow the water to cool for ten minutes and then take the temperature.计算出将产生的膨胀量。Calculate the amount of expansion which will take place.七、by, with的用法七、by, with的用法byby means of用耐火砖可以减少热损耗。Heat losses can be reduced by fireworks.Heat losses can be reduced by lining the furnace with fireworks.The heat loss reduction can be achieved by means of fireworks.withwith the help ofnullThe necessary heat for the carbon-steam and carbon-carbon dioxide reactions is commonly generated by burning part of the carbon in the gasifier.碳和蒸汽以及碳和二氧化碳反应所需的热量通常靠在气化炉中燃烧一部分碳来提供.传动装置上通常有安全销，防止过载。The drive units are normally equipped with shear pins for overload protection.By和 withBy和 withBy means of 后面不能跟动名词短语。√Heat losses can be reduced by means of lining the furnace with firebricks.Heat losses can be reduced by means of firebricks.八、关于“名词+名词”的问题八、关于“名词+名词”的问题①表示原材料 ②表示典型成分 ③表示工作介质an iron pipe = a pipe made of ironoil product = products made of oilmanganese steel = steel which contains manganesecoal minea steam engine = an engine worked by steam④表示工作对象an air compressor = a device for compressing airnull⑤表示用途 ⑥表示方式 ⑦表示所属 ⑧表示关于 ⑨表示形状a drive motor= a motor for driving machinesa foot brake= a brake operated by foot= molecules of waterthe production costwater molecules= the cost concerning productiona star wheel= a wheel shaped like a starnullash contentsurface propertymineral matterrate constantnitrogen dioxideexperiment resultsadsorption mechanismmoisture contentair pressurediamond insert看看下面的名词组合是什么类型satellite communication techniques卫星通讯技术九、很少用“‘s”表示所有九、很少用“‘s”表示所有‘s一般表示生命体的所有，如：Mary’s watch my uncle’s house the cat’s food科技英语中用“名词+of+名词”或“名词+名词”the property of minerals the surface of the earth有时，为方法、技术、反应、定律、方程式等命名，需特别注意有时，为方法、技术、反应、定律、方程式等命名，需特别注意欧姆定律 ohm’s law 牛顿定律 New-ton’s Law 波尔曼技术 Bollman’s technique 一个人 发现者华氏温度计 a Fahrenheit thermometer 本生灯 a Bunhrenheit burner一个人发明者施特芬-波兹曼定律 the Stofan-Boltzman Law 尤利-汤普森反应 the Joule-Thompson effect两个或两个以上人 用复合结构十、定于从句中与which、when连用的介词位置十、定于从句中与which、when连用的介词位置十一、从句的紧缩式十一、从句的紧缩式 当主句与从句是同一主语时， 用“连词+过去分词”，或介词+抽象名词。例：1. 物体放在阳光下时，它会变热。When an object is placed in the sun, it becomes hot .An object becomes hot when it is placed in the sun.An object becomes hot when placed in the sun.null2. 安全火柴只有在被擦时才着火。Safety matches light only when they are stricken.Safety matches light only when stricken.3. 当光线聚集在一点时，会产生大量的热。When light is converged at a point, it would produce large quantity of heat.When converged at a point, the light would produce large quantity of heat.null介词+抽象名词，例：4. Considerable lateral pressure is exerted by the concrete while it is being compacted.在压模时，混凝土产生较大的侧压力。Considerable lateral pressure is exerted by the concrete during compaction.compactcompaction5. after it is separatedafter separationnull连词+形容词，例：6. When necessary必要时Once ……If possible有可能的话一旦While ……当……时 小结 学校三防设施建设情况幼儿园教研工作小结高血压知识讲座小结防范电信网络诈骗宣传幼儿园师德小结 ：可用紧缩式的连词或介词有： When, while, once, if, as, after, during等十二、抽象名词的用法十二、抽象名词的用法抽象名词的来源：动词、形容词1. v. →n.consume, separate, emit, produce, apply, communicate, grow, transmit, install . consumption, separation, emission, production, application, communication, growth, transmission, installationnull抽象名词的来源：动词、形容词2. a. →n.responsible accurate efficientresponsibility accuracy efficiencynullemit→ emissiontransmit→ transmissionconsume→ consumption1. 一年四季的日常用水量不同。The daily consumption of water varies with the season.2.送电时广泛使用变压器。Transformers are widely used in the transmission of electrical power.3. 原子裂变能放出中子。Nuclear fission results in the emission of neutrons.nullinstall→ installationspecify→ specification4.厂家负责安装这种新设备。The installation of the new equipment is the responsibility of the manufactures.5. 所有有关的资料均应在规格中详细说明。All the relevant information should be detailed in the specification. 用抽象名词或动名词代替动词 用抽象名词或动名词代替动词6.用这种方法试验机器需要消耗电力。If machines are tested by this method, there will be some loss of power.The testing of machines by this method entails some loss of power。7.用泵能抽取油箱中的油。The contents of the tank are discharged by a pump.Discharge of the contents of the tank is performed by a pump.testtestingdischargedischarge 用抽象名词或动名词代替从句 用抽象名词或动名词代替从句8.有必要检查一下这些结果是否准确。It is necessary to examine whether these results are accurate.It is necessary to examine the accuracy of these results 。9. 需要有关哪种燃料最合适的情报。Information is needed as to which type of fuel is most suitable.Information is needed as to the most suitable type of fuel.null10. 不清楚这些结果有多么准确。It is doubtful how accurate the results are.The accuracy of the results is doubtful.11. 工作的进展取决于这个机构的效率如何。The progress of the work will depend on how efficient the organization is.The Progress of the work will depend on the efficiency of the organization.十三、as的用法十三、as的用法 “认为”“称为”“表述为”“定义为”“看成是”“作为”“当作”1.This type of motor is know as an induction motor.这种发电机称为感应发电机。2. Electric current may be considered as a flow of electrons through a medium.电流可看成是穿过介质内的一股电子流。3. These materials may be classified as conductors.这些材料可以归在导体类。“以……的形式（或形态）”“以……的形式（或形态）”4.The steam is cooled and condensed as a film of water.蒸汽冷凝成一层水膜。5.The carbon in cast iron is present partly as free graphite.铸铁中的碳部分以自由石墨的形式存在。“正如 … ”、 “如…”、“如图”、“如上”、“如前”“正如 … ”、 “如…”、“如图”、“如上”、“如前”6. As Fig.1.2 shows…… As we have just proved…… As we have stated in the previous chapter……As is shown in the illustration… As is know…… As was mentioned a short time ago…As shown in the table…… As pointed out by professor Smith…As above…… As before…as + 主动句as + 被动句as + 过去分词as + 其它词nullas不翻译出来7. The bridge, as originally planned, would have been too expensive.原来设计的那座桥造价太贵。8. The uranium, as used in the reactor, is the form of a thin rod.在反应堆中用的铀是一种细棒。as不翻译出来 as + such as + such因此9. The earth is a conductor of electricity and as such may form part of an electrical circuit.地球是一种导体，因此就可能形成部分电路。10. A simple governor is dependent on gravity as such it must be kept vertical.一个简单的调速器是依靠重力工作的，因此必须将其竖立放置。因此十四、such that, such as to十四、such that, such as to普通英语中1. Her excitement was such that she shouted.她兴奋地叫起来。2. It was such a lovely day that everybody was feeling happy and cheerful.那是一个如此美好的日子，人人都感到快乐高兴。如此…以至于…3. His illness was not such as to cause anxiety.他的病还没严重到令人忧虑的地步。4. I am not such a fool as to believe that. 科技英语中 科技英语中1. The size of the flow-meter is such that the flow is unaffected by it.流量计的大小是这样设计的，即它不影响流速。或 The size of the flow-meter is such as to have no effect on the flow.2. The job is such that it demands the greatest skill.不翻译出来这是一项需要高度技艺的工作。或 The job is such as to demand the greatest skill. 是这样的， 这种意思十五、完成时的用法十五、完成时的用法多以被动语态出现 描述已经发生的事，时间不明确； 描述不断发生，或到现在为止反复发生的事； 表示“还未”、“自从…一直…”等； 表示“最近”描述已经发生的事，时间不明确描述已经发生的事，时间不明确1.高速公路系统的建设工作已开始。Work has been started on the new system of motorways.2. 研究中用了几种来自不同地方的样品。Samples from different sources have been used in this research.3.研究表明吸烟和肺癌之间有一定的关系。Research has shown a probable connection between smoking and lung cancer.描述不断发生，或到现在为止反复发生的事描述不断发生，或到现在为止反复发生的事4.工程师们遇到许多有关这种材料的问题。Engineers have encountered many problems with this material.5. The pyrite/aqueous interaction has been studied extensively in the past due its importance in extractive metallurgy.由于黄铁矿与水溶液的相互作用在提取冶金中很重要，人们对它进行了大量的研究。表示“还未”、“自从…一直…”表示“还未”、“自从…一直…”6. 这项工程的设计工作还未开始。Design on the project has not been started yet.7. 自从1980年以来一直在进行高速公路的建设。Work on the motorway has been going on since 1980.表示“最近”表示“最近”8. 这家公司最近研制出来一种新型的飞机。The company has just developed a new type of aircraft.9. 由于天气不好，高速公路的建设最近暂停了。Work on the motorway has recently been held up owing to bad weather.十六、动词+后缀当形容词十六、动词+后缀当形容词后缀：-able, -ed, -ing, -ive, -entmachinable steel可加工的钢铁-able, -ible, -uble“可以…”，“可…的”Noticeable effect明显的效果Controllable effect可控制的反应Negligible amount可忽略的数量，一点点后缀：-able, -ed, -ing, -ive, -ent后缀：-able, -ed, -ing, -ive, -entHeated metal加热的金属-ed“被…的”，“被…过的”，“经过…的”Corroded iron生锈的铁Emitted rays放射线treated处理过的Effective remedy有效的医药-ive表示性质、特点等Reactive force反作用力Relative motion相对运动后缀：-able, -ed, -ing, -ive, -ent后缀：-able, -ed, -ing, -ive, -entAbsorbent material吸附剂，吸附型材料-ant, -ent表示性能等Absorbent charcoal活性炭Absorbent paper吸水纸Absorbent cotton吸水棉花，脱脂棉Conducting medium传导介质-ing表示性质、作用等Lubricating oil润滑油Attendant claim附带要求Attendant phenomenon伴生现象十七、常用的前缀十七、常用的前缀前缀： inter-, en-, em-, re-, over-, under-, dis-, de-, im-, sub-, super-, counter-interact相互作用Inter-“在…之间”interconnect互联interwave交织interwine互相盘绕interwork互相配合reuse重用，再用re-“重新”、“再”recharge再充电，再装料recreate再生regrind再磨regroup重组recarbonize再碳化recreate取回，检索，二次呼叫前缀： over-, under-, 前缀： over-, under-, overload超载，超负荷over-“在上”，“过于…的”overall全部，总的overhead架空，高架的overweight超重overgrow蔓生undercurrent低电流under-“在下”、“太少”underground地下的undercapitalize投资紧缩underlay从下面支撑undersize过小undersea海底，水下underload负载不足overseas海外overmany过多overheat过热overwind上卷式overtemperature过热温度underclass经济最底层前缀： dis-, de-, im-, in-,ir-, un-前缀： dis-, de-, im-, in-,ir-, un-disadjust失调dis- 表示反义de- “使不”“脱”“退”disjoin分离discharge放电decarbonize脱碳disconnect解开，折断impure不纯，含杂质im-, in-, ir-, un-“不”、“非”inaccuracy不精密inactive无效，不活动的irregular不规则的irresponsible不负责任的inaccessible不可达的demagnetise退磁defat脱脂，除油dewater脱水immature未成熟的immaterial非物质的irrecoverable不可恢复的前缀： counter-, super-前缀： counter-, super-counteract抵消，抵制counter-“反”、“对”counteradvice反对意见counterbalance配重，平衡力，托盘天平countercharge反控supersonic超声super-“超”、“在…上”、“过”superhard过硬的superheat过热的前缀： sub-, em-,en- 前缀： sub-, em-,en- submarine海底的，潜艇sub-“在…之下”、“子”、“亚”subsurface地下的substandard不合 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 subfile子文件subprogram子程序enlarge扩大，扩展en-, em- +名词或形容词动词ensure确保embed埋，嵌embody包含，具体化，连接，补充subtropical亚热带subpoint投影点subpackage分装subdirectory子目录subnet子网十八、科技文章中较少用“动词+副词”，通常用正规动词十八、科技文章中较少用“动词+副词”，通常用正规动词例：“放出”，用emit，而非 give off “消耗”，用consume, 而非 eat upgives off →emits1. 热的物体以电磁波的形式放能量。A heat body gives off energy in the form of electro-magnetic waves.nullgiven off → emittedeats up → consumes2. 高炉平均每小时消耗三吨燃料。The furnace eats up fuel at the rate of three tons per hour.3. 灼热的金属中放出大量的蒸汽。A certain amount of vapour is given off from the hot metal.若没有相应的动词与之对应，则可使用动词短语若没有相应的动词与之对应，则可使用动词短语处理deal with建立set up拉紧take up起飞take offtake up an occupation就业set up in business开始营业set up business经营set up a business开业The aircraft will take off at ten o’clock.作业：汉译英作业：汉译英1、金属就是像铜、铁之类的东西。（as） 2、液态水变成蒸汽，这就叫做蒸发。 3、金属具有许多优良的性能，这在前面已经讲到了。 4、塑料具有许多良好的性能，因此在工业上应用很广泛。（动名词） 5、任何发生这种氧化的地方，总有热产生。 6、用煤炼焦（make coke）时，还产生副产品。 7、推力一停住，物体就停止向上运动。（抽象名词） 8、必须找到一种能运更大吨位（tonnage），同时又节省宝贵人力的新设备。1.3 科技英语中的一些常用句型1.3 科技英语中的一些常用句型一、make +名词+形容词一、make +名词+形容词这样会使问题变得容易些. This makes the problem easy/easier. 这样能使金属更硬些. This makes the metal harder/hard. 这样能使金属变长。 This makes the metal longer. = This lengths the metal.make +名词+形容词make +名词+形容词这样能使螺栓更紧些。 This makes the screw tighter. = This tightens the screw. 这样能使洞更深些. This makes the hole deeper. = This deepens the hole.二、enable, allow, make…+ 不定式二、enable, allow, make…+ 不定式Enable, allow, make, cause, permit Safety valves allow/permit the steam to escape. 安全阀能使蒸气（从锅炉中）排出 好的生产方法能使工厂生产更多的汽车。 Good production methods enable the factory to manufacture more cars 显微镜能使科学家们观测非常小的物体。 A microscope enables the scientists to examine very small objects.enable, allow, make…+ 不定式enable, allow, make…+ 不定式 enable, allow, make, cause, permit 温度计能使医生（为病人）测体温。 A thermometer enables the doctor to measure body temperature. 伸缩接头能使管子延长或缩短。 Expansion joints allow/permit the pipes to expand or contract. 安全阀能使蒸气（从锅炉中）排出。 Safety valves allow/permit the steam to escape. enable, allow, make…+ 不定式enable, allow, make…+ 不定式热使金属熔化。 The heat caused the metal to melt. = The heat makes the metal melt. 火车速度太快，使其在弯道处出轨了。 The speed of the train caused it to leave the rails on the curve. = The speed of the train made it leave the rails on the curve.三、It is + 形容词+不定式三、It is + 形容词+不定式It is was seems appears proves becomeseasyto do sth.+++It is possible impossibleto do sth.++It is necessary unnecessaryto do sth.++It is + 形容词+不定式It is + 形容词+不定式commonIt is usual unusualto do sth.++It is to do sth.++It is useful uselessto do sth.++这些形容词都是带有主观评价色彩的，如： easy， possible / impossible， useful / useless ， necessary / unnecessary ， usual / unusual四、It is + 形容词+ that四、It is + 形容词+ thatIt is evident that these currents will generate heat in the core of the magnet.It is likely that eddy currents will be produced in the core of the magnet. obvious clear possiblethat 引出一个主语从句，it 是无人称主语例：显然，这些电流会使磁铁中心产生热。例：在磁铁中心很可能会产生涡流电流。It is + 动词+ thatIt is + 动词+ thatIt should be noted that this energy can not be destroyed, only changed into other forms. realizedIt is assumed that the gas temperature in the cylinder is constant.例：需要注意/明白的是，这种能量是不能消失的， 只能转化成其它形式。例：假定气缸中气体温度为定值。It is + 动词/形容词+ thatIt is + 动词/形容词+ thatIt is desirable that these currents should be eliminated as far as possible.It is decided that the production should begin in a few months. essential arranged planned例：最好尽可能地把这些电流除掉。例：已经决定在几个月内开始生产。nullIt is known that …… proved例：已知，…… 众所周知，…… 据证，……It should be noted that …… will例：应当注意到/应该看到/应当知道，… realized noticed appreciatedIt can be shown that ……例：可以证明，… proved demonstrated五、句末 + ing 子句五、句末 + ing 子句 连接两个陈述句的一种方法 ① 同 and 的意思一样； ② 相当于 since 的意思，进一步解释； ③ 说明第一句话的后果或时间的接续。例：The starter motor is switched off, the engine accelerating under its own power.关闭启动马达，发动机依靠它自己的动力加速。例： The normal type of crank shaft is used, the upper pistons being operated by crossheads.使用标准曲（柄）轴，上活塞便由十字头操作。andand句末 + ing 子句句末 + ing 子句例： The proton is the opposite of the electron, being a particle of positive electricity.质子与电子性质相反，它是一种带正电的离子。例： Mercury is most commonly used in thermometers, having a constant coefficient of expansion.由于水银的膨胀系数是常数，它常常用于温度计中。sincesincenull通常可以在第二个句子（子句）前 加一个词，thus 或 thereby说明第一句话的后果例： The rivet contracts as it cools, drawing the plates together.铆钉冷却收缩时，便把钢板禁固在一起。例： The rivet contracts as it cools, thereby drawing the plates together.null六、引出问题的几种方法六、引出问题的几种方法用 “It is necessary to …” It is necessary to determine whether those results are correct. 用 “as to” 引出 A decision should be taken as to which data is correct. Research is going on as to how the industrial pollution can be controlled. 用“It is doubtful / not clear / unknown how …”引出 It is doubtful how accurate these results are. 或 It is not clear how accurate these results are.引出问题的几种方法引出问题的几种方法用 “…depend on what … / how…”引出 The progress