自动化专业英语unit 2 A1.ppt

Unit2,Resistor,CapacitorandInductor,Resistor，CapacitorandInductor,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Ifabatteryisconnectedacrossaconductingmaterial，acertainamountofcurrentwillflowthroughthematerial.Thiscurrentisdependentonthevoltageofthebattery,onthedimensionsofthesample,andontheconductivityofthematerialitself.1TheoppositiontocurrentiscalledelectricalresistanceandisrepresentedbythelettersymbolR.Theunitofresistanceistheohm,atermthatisoftenexpressedbyusing.Oneohmisdefinedasthatamountofresistancethatwilllimitthecurrentinaconductorisoneamperewhenthevoltageappliedtotheconductor,Unit2Resistor,CapacitorandInductor,Resistors,Resistor,CapacitorandInductor,电阻假若将电池连接在导电材料上，一定数量的电流将流过此材料，流过材料的电流取决于电池的电压、材料的截面积和材料自身的电阻率。对电流的阻力叫电阻，用字母符号R表示。电阻的单位是欧姆通常用表示。l欧姆的定义为：当加到导体上的电压为l伏特时，将导体中的电流限制在1安培所需要的电阻值。,isonevolt.Largeramountsofresistancearecommonlyexpressedinkiloohm(K)andinmegohm(M).Theresistorsaremadefromcarbonmixtures,metalfilms,orresistancewireandhavetwoconnectingwiresattached.Variableresistors,withanadjustableslidingcontactarm,areoftenusedtocontrolvolumeonradiosandtelevisionsets.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,较大的电阻值常用千欧(K)和百万欧姆(M)表示。电阻可以由碳混合物、金属薄膜或电阻丝制成，它有两个连线接头。常常用带有滑动臂的可变电阻器来控制收音机和电视机的音量。,Electricalenergycanbestoredinanelectricfield.Thedevicecapableofdoingthisiscalledacapacitororacondenser.Capacitorsconsistoftwometalplatesthatareseparatedbyallinsulatingmaterial.2Ifabatteryisconnectedtobothplates,anelectricchargewillflowforashorttimeandaccumulateoneachplate.Ifthebatteryisdisconnected，thecapacitorretainsthechargeandthevoltageassociatedwithit.3,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Capacitors,电容器电能可以储存在电场中，能够储存电能的装置叫电容器。电容器是由被绝缘材料分开的两个金属板组成。如果电池被连接在两个金属板上，电荷将经过很短的流动而汇集在一个电极板上。假若断开电池，电容器将保持电荷以及与电荷相关的电压。,Theabilityofacapacitortostoreelectricalenergyistermedcapacitance.Thecapacitanceisdirectlyproportionaltothedielectricconstantofthematerialandtotheareaoftheplatesandinverselytothedistanceoftheplates.4Itismeasuredinfarads.Whenachangerofonevoltpersecondacrossitcausesthecurrentofoneamperetoflow,thecondenserissaidtohavethecapacitanceofonefarad.However,faradistoolargeaunittobeusedinradiocalculation,somicrofarad(10-6farads)andthepicofarad(10-12farads)aregenerallyused.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,电容器储存电能的能力叫电容。电容器的电容量与介质的介电常数及平板的面积成正比，与平板间的距离成反比，其大小用法拉表示。当电容器两端的电压以每秒1伏的速率变化，产生的电流为1安培，就称电容器的电容量为1法拉。在无线电方面的计算中，法拉的单位太大，因此常用微法(法拉)和皮法(法拉)。,lnductorsconsistofaconductingwirewoundintotheformofacoil.Whenacurrentpassesthroughthecoil,amagneticfieldissetuparounditthattendstoopposerapidchangesincurrentintensity.5AllcoilshaveinductanceAcoilofmanyturnswillhavemoreinductancethanoneoffewturns.Alsoifacoilisplacedonanironcoreitsinductancewillbegreaterthanitwaswithoutthemagneticcore.Theunitofinduct-,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Inductor,电感电感是由绕成线圈形状的导线组成。当电流通过线圈时，在线圈周围将产生磁场，它将阻止电流的快速变化。一切线圈，都有电感。匝数多的线圈比匝数少的线圈电感更大。而且，假若线圈中放一个铁芯它的电感将比没有铁芯的线圈的电感更大。,anceishenry.Acoilhasaninductanceofonehenryifaninducedemfofonevoltisinducedinthecoilwhenthecurrentthroughitchangesattherateofoneampereparsecond.6Valuesofinductanceusedinradioequipmentvaryoverawiderange.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,电感的单位是亨利。当流过线圈的电流以每秒1安培的速度变化时，如果线圈中感应出1伏特感应电动势，那么，线圈的电感就是1亨利。用于无线电设备的电感值的变化范围很大。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,NewWordsandPhrases,capacitorkpsitn.电容器capacitancekpsitnsn.电容；电流容量inductorindktn.授职者；感应器inductanceindktnsn.感应系数；自感应；电感dimensiondimenn,dai-n.维；尺寸；vt.标出尺寸adj.规格的conductivity,kndktivitin.传导性；导电性；传导率opposition,pzinn.反对；敌对；相反；反对派carbonka:bnn.碳；碳棒；复写纸adj.碳的；碳处理的filmfilmn.胶卷；薄膜；轻烟；膜层vi.生薄膜；volumevlju:mn.体积；卷；册；音量；大量；adj.大量的,wirewain.金属丝；电线；电报vt.拍电报；给装电线condenserkndensn.冷凝器；压缩器；聚合器；电容器proportionalprup:nladj.成比例的；相称的，n.比例项insulateinsjuleitvt.隔离，使孤立；物使绝缘，使隔热insulatingadj.绝缘的；隔热的（insulate的ing形式）accumulatekju:mjuleitvi.累积；积聚vt.积攒disconnect,disknektvt.拆开，使分离vi.断开retainriteinvt.保持；雇；记住dielectric,daiilektrikadj.非传导性的；诱电性的n.电介质；绝缘体inverselyinv:sliadv.倒转地；相反地；反比例地,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,faradfrdn.法拉（电容单位）microfarad,maikrufrdn.微法拉（电容量的实用单位）picofaradpaiku,frdn.微微法拉（百亿分之一法拉）coilkilvt.盘绕，把卷成圈vi.成圈状n.卷；线圈intensityintenstin.强烈；强度；亮度；紧张；集中程度corek:n.核心；果心；要点；磁心(ironcore铁芯)inducedindju:stadj.感应的；引诱的（induce的过去分词）henryhenrin.亨(利)电感单位，略作Hpl.henrys,henries,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,variableresistor可变电阻器slidingcontact滑动触点electriccharge电荷dielectricconstant介电常数，电容率magneticfield磁场emfabbr.n.电动势(ElectromotiveForce),Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,TechnicalTerms,1.capacitancekpsitnsn.电容；电流容量；机械容量1)relatedphrases：inputcapacitance输入电容equivalentcapacitance等效电容capacitancecoupling电容耦合capacitancerelay电容式继电器shantcapacitance分流电容；并联电容anodecapacitance阳极电容howtheyareappliedinelectronicindustry.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,WordStudy,2）Features:Highvoltage,smallcollectoroutputcapacitance.特点:耐压高,集电极输出电容小。3）Arethereanyprecautionswhenadjustingthecapacitancevalue?调整电容值时有哪些注意事项?4）Theformulaofcapacitanceandvoltagedependenceofpowerhasbeeneduced.推导出了功率随电容和电压变化的计算公式。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2dimensionn.维；尺寸；容积vt.标出尺寸adj.规格的relatedphrases：angulardimension角度标注；角度大小lineardimension线性尺寸verticaldimension垂直尺度fitdimension配合尺寸underdimension尺寸过小dimensionscale标注比例,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2）Lengthisonedimension,andwidthisanother.长是一种度量，宽又是一种度量。3)Theproblemofthevehiclevelocitydetectionisresolvedbyonedimensionvideotracing.通过一维视频跟踪的方式，解决了车辆速度检测的难题。4)Thefinancialdimensiontomarkethigh-qualityproducts,qualityservicetowincustomers.维融以优质的产品占领市场，以优质的服务赢得了客户。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,3.volumen.体积；卷；音量；大量；adj.大量的vt.把收集成卷1)relatedphrases：volumelabel卷标号boundvolume合订本volumecontrol播放控制台volumefraction体积分率；容积比criticalvolume临界容积strokevolume冲程容积；心搏量,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2）Theprogressschedulecompiledonthebasisofvolumeproduction.根据批量产品生产预定时间表编制的进度计划；3）Largevolumeofdataweregathered.人们收集了大量的资料。4）Webuyinvolumeandcontractearlytogetthebestprices.大宗采购和尽早签订合同以获得最低货源价格。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,4accumulatekju:mjuleitvi.累积；积聚vt.积攒1)relatedphrases：accumulateexperience获取经验accumulatepoints积分accumulatepick多重选择accumulatefunds积累资金accumulatedose总剂量，累计剂量,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2)WhenweaccumulatemoreandmoresuchdifferencesbetweenChineseandEnglishconsciously,wewillthinkinEnglishwhenwespeakEnglish.当我们有意识地积累了越来越多的类似的英汉差异之时，我们就开始用英语思维来表达事物了。3）Overall,therefore,thecountrydidnotaccumulatesubstantialforeigncurrencyreserves.因此，总体来看，中国没有积累很大的外汇储备。4）Accumulateandsummarizeallkindsofindexcompleted.Dothebasicandpreparationjoboffinancialbudget.积累总结各项指标完成情况的资料，做好财务预算的基础准备工作。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,5intensityintenstin.强烈；强度；亮度；紧张；集中程度1)relatedphrases：fieldintensity磁场强度earthquakeintensity地震强度radiantintensity发光度,辐射率,辐射强度loadingintensity荷载强度intensityofmarketposition市场地位的集中程度,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2)Compact,highmagneticinductionintensityandlongcoilservicelife.结构紧凑，磁感应强度高，线圈使用寿命长。3)Thisreducesthelaborintensity,reducepollution,conservewaterresources.这就降低了劳动强度、减少污染、节约水资源。4)Compact,highmagneticinductionintensityandlongcoilservicelife.结构紧凑，磁感应强度高，线圈使用寿命长。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,6.inducedindju:stadj.感应的；v.引诱；说服（induce的过去分词)1)relatedphrases：inducedcircuit感应电路；inducedcurrent感生/应电流；inducedradiation感应(生)放射性；inducedfailure诱发故障；inducedoperation诱导运算,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2）Nauseaanddizzinessinducedbymotion,asintravelbyaircraft,car,orship.晕船（车）：由运动引起的恶心和眩晕，如乘飞机、小汽车或轮船。3）Theroadtrafficaccidentsinducedbyfatiguedrivingwillleadtoseverepersonalcasualtyandpropertyloss.疲劳驾驶引发的道路交通事故导致了严重的人身伤亡和财产损失。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,8ironcore：铁芯magneticcore：磁芯corek:n.果心,核心,要点vt.挖去(水果的)果心1)relatedphrases：cablecore电缆芯线；电缆心corediameter芯样直径；根径corepin心型梢；中心销corecompetence/competenc核心能力；关键才能,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2）Theearthhaveacoreandamantlearoundit.地球的中心是地核，地核的周围是地幔。3）Teamspiritisthecoreofenterpriseculture.团队精神，是企业文化的核心。4）Themonopolypricingpoweristhecoremeaning.垄断最核心的意义就是定价权。5）Atthecoreofcompetitiveness,likehowtoattractnewcompetitiveness.在核心竞争力不足的时候，就想怎么吸引新的竞争力。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,1.Thiscurrentisdependentonthevoltageofthebattery,onthedimensionsofthesample，andontheconductivityofthematerialitself.流过材料的电流取决于电池的电压、材料的截面积和材料自身的电阻率。句中bedependent(on)：“由决定，取决于”，又如：1)Seatingloadandtightnessisdependentonbackpressure.阀座密封负载和紧密性与反压力相关。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Languagepoints,Tourismisaresourceandtheenvironmentisheavilydependentontheindustry.旅游业是一个对资源和环境严重依赖的行业。3)Mayyoufindenoughinnerstrengthtodetermineyourownworthbyyourself,andnotbedependentonanothersjudgmentsofyouraccomplishments.愿你能充分发掘自身潜能，以决定你的价值所在，不要让别人的评判埋了你的成绩。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2.bedefinedas：“被定义为”，后接宾语，或“that”引导的宾语从句。如：1）Oneohmisdefinedasthatamountofresistancethatwilllimitthecurrentinaconductorisoneamperewhenthevoltageappliedtotheconductorisonevolt.l欧姆的定义为：当加到导体上的电压为l伏特时，将导体中的电流限制在1安培所需要的电阻值。句中第一个that作定语，第二个that引导定语从句，该从句本身包含了一个when引导的时时间状语从句。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2）Amoleculemaybedefinedasthesmallestparticleofmatterthatcanexistwithoutchangingitsnature.分子可以被定义为物质在不改变其性质的情况下而能存在的物质的最小粒子。3)Motionmaybedefinedasacontinuouschangeofabodyinpositionwithrespecttosomeotherbodyorbodiesatrest.运动可定义为一个物体相对于另一个或几个静止物体在位置上的连续变化。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,3.Capacitorsconsistoftwometalplatesthatareseparatedbyallinsulatingmaterial.电容器是由被绝缘材料分开的两个金属板组成。句中that引导定语从句，修饰twometalplates，consistof表示“由组成”，又如：1）Auditrisksconsistofintrinsicrisk,controlriskandexaminationrisk.审计风险由固有风险、控制风险和检查风险构成。2）Modernwindfarmsconsistofturbinesthatgenerateelectricity.现代风力农场由发电的涡轮机组成。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,4.Ifthebatteryisdisconnected，thecapacitorretainsthechargeandthevoltageassociatedwithit.如果断开电池，电容器将保持电荷以及与电荷相关的电压。句中retain表示“保持；雇；记住”的意思。又如：1）Helpyourskinretainmoisture.帮助皮肤保持水分。2）Retainyouroriginalreceiptasproofofpurchase.请保留您的原始发票作为购买证明。3）Moneyhastwofunctions,oneistoretainthevalueofwealth,theotherisanexchangevalueofthewealth.金钱有两个职能，一个是保留财富价值，一个是交换财富价值。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,5.Thecapacitanceisdirectlyproportionaltothedielectricconstantofthematerialandtotheareaoftheplatesandinverselytothedistanceoftheplates.电容器的电容量与介质的介电常数及平板的面积成正比,与平板间的距离成反比。a）bedirectlyproportionalto：“与成正比”b）beinverselyproportionalto：“与成反比”又如：1)Theresistanceofathinfilm/coatingisdirectlyproportionaltotheresistivity,andinverselyproportionaltothethickness.薄膜镀膜的电阻与该镀镆的电阻系数成正比,与厚度成反比.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2)Themagnitudeoftheforceisfoundtobeinverselyproportionaltothedistancebetweentheconductors.人们发现力的大小与施力者之间的距离成反比。6.Whenacurrentpassesthroughthecoil，amagneticfieldissetuparounditthattendstoopposerapidchangesincurrentintensity当电流通过线圈时，在线圈周围将产生磁场，它将对抗电流的快速变化。句中that引导定语从旬，修饰amagneticfield，it指代thecoil。opposevt.vi.表示“反对；对抗，抗争”，,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,又如：1）Smallbanksandsomestateofficialsstronglyopposetheplan.小银行以及某些州的官员强烈反对该方案。2）Weopposeallformsofhegemonismandpowerpolitics.反对各种形式的霸权主义和强权政治。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,7.Alsoifacoilisplacedonanironcoreitsinductancewillbegreaterthanitwaswithoutthemagneticcore.而且，如果线圈中放一个铁芯，它的电感将比没有铁芯的线圈的电感大。句中than引导一个比较状语从句。inductanceindktnsn.“感应系数；自感应；电感”，又如：1）DCvoltageisdeterminedbyACvoltage,inductanceontheACside,andload.直流侧直流电压是由交流电压、电感及负载决定的。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,2）TheeffectsofinductanceandcapacitancemakeitnecessarytocarefullydesignallACtransmissionsystems.电感和电容的影响，使人们必须精心地设计所有的交流输电系统。Acoilhasaninductanceofonehenryifaninducedemfofonevoltisinducedinthecoilwhenthecurrentthroughitchangesattherateofoneamperepersecond.当流过线圈的电流以每秒1安培的速度变化时，如果线圈中感应出1伏特感应电动势，那么，线圈的电感就是1亨利。attherateof“以的速度/速率/比率/变化率/频率”,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,又如：1）Incomefrompropertytransactionsshallbefiledandtaxedattherateof35%.财产交易所得按35%扣缴率申报纳税。2）Profitsfromoccasionaltradeshallbefiledandtaxedattherateof30%.一时贸易的盈余按30%扣缴率申报纳税。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,I.Answerthefollowingquestionsaccordingtothetext.Whatiscalledaresistor?Whatistheunitofresistance?Whatistheusageofvariableresistors?,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Exercises,oppositiontocurrentiscalledelectricalresistance.,Theresistorsaremadefromcarbonmixtures,metalfilms,or,resistancewireandhavetwoconnectingwiresattached.The,areoftenusedtocontrolvolumeonradiosandtelevisionsets.,Variableresistors,withanadjustableslidingcontactarm,3.Whatiscalledacondenser?Whichelementsdocondensersconsistof?4.Howtodefineonefaradofthecapacitance?,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Capacitorsconsistoftwometalplatesthatareseparatedbyall,Thedevicecapableofdoingthisiscalledacapacitororacondenser.,insulatingmaterial.,havethecapacitanceofonefarad.,Whenachangerofonevoltpersecondacrossitcauses,thecurrentofoneamperetoflow,thecondenserissaidto,5.Whatareinductorsmadeupof?Howtodefineonehenryofaninductance?,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,rateofoneampereparsecond.,Inductorsconsistofaconductingwirewoundintotheformofacoil.,Acoilhasaninductanceofonehenryifaninducedemfofonevolt,isinducedinthecoilwhenthecurrentthroughitchangesatthe,IIFillinthemissingwordsaccordingtothetext1.Thiscurrentdependsonthevoltageofthebattery,onthe_ofthesample，andonthe_ofthematerialitself.2.A_isadevicedesignedtohavecapacitance.3.Ohmisusedasaunitof_.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,dimensions,conductivity,capacitor,resistance,4.Thelargeristheemf,themore_thecapacitorstores5.Whenachangerofonevoltpersecondacrossitcausesthecurrentofoneamperetoflow,the_issaidtohavethecapacitanceofone_.6.The_aremadefromcarbonmixtures，metalfilms，orresistancewireandhavetwo_wiresattached.,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,capacitance,condenser,farad,resistors,connecting,IIITranslatethefollowingsentencesintoEnglish1.可变电阻器常用来控制收音机和电视机的音量。2.电容器存储电能的能力叫电容。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Variableresistorsareoftenusedtocontrolvolumeonradios,andtelevisionsets.,Theabilityofacapacitortostoreelectricalenergyistermed,capacitance.,3.任何电感都是由线圈组成，线圈的匝数越多，电感越大。4.电容器的电容量与介质的介电常数及平板的面积成正比,与平板间的距离成反比。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,thematerialandtotheareaoftheplatesandinverselytothe,lnductorsconsistofaconductingwirewoundintotheformofacoil.,Acoilofmanyturnswillhavemoreinductancethanoneoffewturns.,Thecapacitanceisdirectlyproportionaltothedielectricconstantof,distanceoftheplates.,词义的确定英汉两种语言都有一词多类、一词多义的现象。一词多类是指一个词往往属于多个词类，具有几种不同的意义。如display一词，既可做名词“显示（器）”，又可以作形容词“展览的、陈列用的”，还可做动词“显示、表现”等意思。一词多义是说同一个词类中，往往有几个不同的词义。如power一词，做名词时，其汉语意思为“电力、功率、次方”等。在英汉翻译过程中，我们在弄清句子结构后就要善于选择和确定句子中关键词的意义。选择和确定词义通常从以下几个方面入手：,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,TranslatingSkills,一、根据词类确定词义选择某个词的词义时，首先要确定这个词在句中应属于哪一种词类，然后再进一步确定其词义。下面以display为例：Here,youhavetheoptionofdefiningyourowndisplayvariants.这里，你有权定义你自己的显示变式。(display为名词)Often,itisbesttodisplaymaterialsonaninformationtable.通常，最好是把资料放在提供各类资讯的桌子上展示。(display为动词),Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Thereversesideofacontrolpanel,displaypanel,orthelike;thesidewiththeinterconnectingwiring.(display为形容词)控制面板、显示面板或类似的面板的反面，即带有互连接线的那一面。二、同一词类表达不同词义英语中同一个词，同一类词，在不同的场合，往往具有不同的含义。此时,必须根据上下文的联系及整个句子的意思加以判断和翻。例如as这一连词：Thevolumevariesasthetemperatureincreases.体积随着温度增加而变化。(as引导时间状语从句)Asheatmakesthingsmove,itisaformofenergy.因为热能使物体运动，所以热是能的一种形式。(as引导原因状语从句),Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,三、根据单词搭配情况确定词义英译汉时，不仅必须根据上下文的联系理解词义，还需要根据词的搭配情况来理解词义。尤其在科技文献中，由于学科及专业不同，同一个词在不同的专业中具有不同的意义。比如：Thefifthpoweroftwoisthirty-two.二的五次方是三十二。(数学)Withthedevelopmentofelectricalengineering,powercanbetransmittedoverlongdistances.随着电气工程的发展,电力能输送得非常远。（电学）Frictioncancausealossofpowerineverymachine.摩擦能引起每一台机器功率的损耗。（物理学）,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,四、根据名词的单复数选择词义英语中有些名词的单数或复数表达的词义完全不同。例如：名词单数词义复数词义facility简易，灵巧设施，工具charge负荷，电荷费用spirit精神酒精Althoughtheylost,theteamplayedwithtremendousspirit.那队输是输了，但却表现了极其顽强的精神。Whisky,brandy,ginandrumareallspirits.威士忌、白兰地、杜松子酒和朗姆酒都是烈酒。,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,HowToUseaTester,ThisinstrumentisdesignedtouseformeasuringDCvoltages,measuringACvoltages,measuringresistance,conductivitytestanddiodetest.Ithas3.5digitsliquidcrystaldisplay.Soitiscalledadigitalmulti-meter.Thefollowingisillustratingitsoperation.MeasuringDCvoltages(SeeFig.2-1)SetthefunctionswitchtoDCVConnectthetestleadstothecircuittobemeasuredReadthedisplay,Unit2Resistor,CapacitorandInductor,Resistor,CapacitorandInductor,该仪表是设计用来测量直流电压、交流电压、电阻导电性能和二极管测试的。该仪表具有3位数字的液晶显示，因此它也被称作数字多用表。该仪表的使用方法示例如下：直流电压的测量（见图2-1）（最大输入电压为直流500V）功能开关置于DCV。测试表笔接在被测电路上。读显示值。,Note：“-”(minussign)isdisplayedwhe