Unit3 The World of science Using language-外研版高中英语必修第三册

Unit3theworldofscienceUsinglanguage现在完成时现在完成时表示过去的动作或存在的状态对现在造成的影响或结果，过去的这个动作或状态也有可能持续下去。用法：表示一个动作刚刚结束或完成，但这个动作所造成的状态或影响依然存在，即表示过去的动作对现在的影响或结果，强调现在的情况，常与副词just,already（多用于肯定句或疑问句）,yet（常用于疑问句或否定句句尾）连用。表示从过去到现在曾经发生过或经历过某事，表达一种经验或经历，常与副词ever，never，once，twice，before等连用。常与for或since连用。For后面接一段时间；since后接时间点或表示过去时间的时间状语从句。特殊句型【This/That/Itisthefirst/second/third…timethat…】【This/That/Itisthe+形容词最高级+名词+从句】【Itis/hasbeen…since...(过去式)】

ThisisthefirsttimethatI______________(watch)theplay.ThisisthebestfilmthatI______________(see).It___________(be)sixyearssinceIcamehere.

havewatchedhaveseenhasbeen现在完成时练习一1、Duringthelastthreedecades,thenumberofpeopleparticipatinginphysicalfitnessprograms_____________(increase)sharply.2、Afterseveralyearsofobservation,theresearchgroup__________(arrive)attheconclusionthatlanguageacquisitionisfasterwhenstudentsareexposedtothesituationwhereitisspoken.3、Simon_____________(attend)hisfatherforsuchalongtimethatheunderstandsalmosteverygestureofhisfather’s.4、Itisthefirsttimethatthelocaleducationauthority________(make)suchstrictrequirementsongoing-to-schooltimeforprimaryandmiddleschoolstudents.5、Overthelastfewyears,thenumberofstudentsparticipatinginvolunteerprograms______________(increase)sharplyinourschool.hasincreasedhasarrivedhasattendedhasmadehasincreased6、Researchersbelievethatsince2010anaverageofnearly35,000elephants_____________(kill)annuallyonthecontinent.7、Withthehelpofhightechnology,moreandmorenewsubstances_______________(discover)inthepastyears.8、Inthepastfewcenturies，thelighthousesalongNorthCarolina’scoast__________________(recognize)assignsofsafetyfortravelersatsea.9、Icomplained

tothemanagerofthehotelaboutthepoorservicelastweek,butuptonow，I____________(receive)hisreply.havebeenkilledhavebeendiscoveredhavebeenrecognizedhaven'treceived10、Largequantitiesofwater,aswellassomeothertimelyhelpincludingamedicalteam_______________(offer)sincetheseriousdroughthitYunnanProvince.11、Morethanoneworker_________________（send）tothetrainingcentertoimprovetheirworkingskillsinthepastthreeyears.12、Since2011,thecountry___________(grow)morecornthanrice.13、Regularlyeatingoutseemsto_____________(become)commonformanyyoungpeopleinrecentyears.hasbeensenthasgrownhavebecomehavebeenoffered现在完成时练习二将下面划线句子改为现在完成时被动语态。Withinthenext80years,ourlivesmaybechanged

beyondrecognitionby3Dprinting.Ithasalready

affectedmanythingsinourlives,rightdowntothe

foodweeat.Forinstance,somerestaurantsinLondon

haveserved3D-printedhamburgerstocustomers.

Butperhapsthemostsignificantsuccessthatpeople

haveachievedtodateisinmedicine.Theyhavemade

humanbodyparts,includingabeatingheart,with3D

printingtechnology.Anditisnotjusthumanswho

arebenefiting-inBrazil,peoplehavegivenanew

3D-printedshelltoaturtleinjuredinaforestfire!参考答案：1.Manythingsinourliveshavealreadybeenaffected.2.3D-printedhamburgershavebeenservedtocustomersinsomerestaurantsinLondon.3.Butperhapsthemostsignificantsuccessthathasbeenachievedtodateisinmedicine.4.Humanbod