專四語法解析

情態(tài)動詞注意情態(tài)動詞完成式的用法有兩方面的含義：1.表示已經(jīng)發(fā)生的情況(1)musthave+過去分詞，表示對已發(fā)生情況的肯定推測，譯為“(昨天)一定……”。如：MypainmusthavebeenapparentthemomentIwalkedintotheroom,forthefirstmanImetaskedsympathetically:“Areyoufeelingallright?”

(2)can’t/couldn’thave+過去分詞，表示對已發(fā)生情況的否定推測，譯為“(昨天)一定沒……”。如：Marycouldn’thavereceivedmyletter;otherwiseshewouldhaverepliedbeforenow.(3)may/mighthave+過去分詞，表示對已發(fā)生的事情做不肯定、可能性很小的推測，或事實上根本沒發(fā)生，譯為“也許……”。如：AtFloridaPower’sCrystalRiverplant,apotentiallyseriousleakageofradioactivewatermayhavebeenunknowinglycausedbyanelectrician.2.表示虛擬語氣(1)needn’thave+過去分詞，表示做了不必做的事，譯為“其實沒必要……”。如：Asitturnedouttobeasmallhouseparty,weneedn’thavedressedupsoformally.(2)should/shouldnothave+過去分詞，表示應(yīng)該做某事但實際上未做，或本不應(yīng)該做但實際上做了,譯為“本(不)應(yīng)該……”。如：Iregrethavinglefttheworkunfinished;Ishouldhaveplannedeverythingaheadcarefully.(3)oughttohave+過去分詞，表示動作按理該發(fā)生了，但實際上未發(fā)生，譯為“該……”，與should的完成式含義類似。如：Theporteroughttohavecalledthefire-brigadeassoonashesawthefireinthestock,whichwentupinsmoke.(4)couldhave+過去分詞，表示過去本來可以做但卻未做，譯為“完全可以……”。如：Whatyousaidisright,butyoucouldhavephraseditmoretactfully.(5)may/mighthave+過去分詞，表示過去可以做但實際未做，譯為“(那樣)也許會……”。如：Itmighthavebeenbettertoincludemorepunchystatisticsandphotosofequipmentintheintroductiontofurtherassistfirst-timeofficeautomationmanagers.3.幾個情態(tài)動詞?？嫉木湫?1)may/might(just)aswell“不妨，最好”，與hadbetter相近。如：Sincetheflightwascancelled,youmightaswellgobytrain.(2)cannot/can’t…too…“越……越好，怎么也不過分”。注意這個句型的變體cannot…over…。如：Youcannotbetoocarefulwhenyoudriveacar.Thefinalchaptercoversorganizationalchangeanddevelopment.Thissubjectcannotbeoveremphasized.(3)usedn’t或didn’tuseto為usedto(do)的否定式。(4)should除了“應(yīng)該”一層意思外，大綱還規(guī)定要掌握其“竟然”的意思。如：Ididn’texpectthatheshouldhavebehavedlikethat.復(fù)合句——名詞性從句一個句子起名詞的作用，在句中做主語、賓語／介詞賓語、表語、同位語，那么這個句子就是名詞性從句。1.what/whatever的用法考生應(yīng)把握：what是關(guān)系代詞，它起著引導(dǎo)從句并在從句中擔(dān)當(dāng)一個成分這兩個作用。如：Theylosttheirwayintheforest,andwhatmademattersworsewasthatnightbegantofall.(what既引導(dǎo)主語從句又在從句中做主語)Waterwillcontinuetobewhatitistoday—nextinimportancetooxygen.(what既引導(dǎo)表語從句又在從句中做表語)2.whoever和whomever的區(qū)別whoever和whomever相當(dāng)于anyonewho，用主格與賓格取決于其在從句中做主語還是做賓語。如：Theyalwaysgivethevacantseatstowhoevercomesfirst.(whoever在從句中做主語)3.有關(guān)同位語從句的問題(1)引導(dǎo)詞通常為that,但有時因名詞內(nèi)容的需要，也可由whether及連接副詞why,when,where,how引導(dǎo)。that不表示任何意義，其他詞表示時間、地點、原因等。如：Theproblem,whereIwillhavemycollegeeducation,athomeorabroad,remainsuntouched.

(2)同位語從句有時與先行詞隔開，注意識別。如：Evidencecameupthatspecificspeechsoundsarerecognizedbybabiesasyoungas6monthsold.4.whether與if在引導(dǎo)名詞性從句時的區(qū)別(1)主語從句只能用whether引導(dǎo)；(2)whether一般多用于賓語從句的肯定式，而if引導(dǎo)的從句可以有否定式；(3)whetherornot可以連在一起用，而ifornot則不能，ornot只能放在句末；(4)whether可以引導(dǎo)介詞賓語從句，if則不能；(5)賓語從句提至謂語前面時，只能用whether引導(dǎo)；(6)在question,ask后面一般只用whether，question的同位語從句也用whether引導(dǎo)；(7)后接不定式時，只能用whether。5.動詞believe,expect,fancy,imagine,suppose,think后的賓語從句如為否定式，一般將否定詞轉(zhuǎn)移到主句謂語上。復(fù)合句——副詞性(狀語)從句副詞在句中起狀語作用，故如果起狀語作用的部分為一個句子，那么該句便是副詞性從句，也稱狀語從句。狀語從句可細分為：時間、地點、條件、原因、讓步、目的、結(jié)果、比較、方式等。狀語從句的測試重點為：考查考生對主從句之間邏輯意義關(guān)系的把握，看其是否能選擇正確的從屬連詞。1.條件狀語從句的常考知識點(1)if與unless的用法。if和unless都是引導(dǎo)條件狀語從句的連詞，考生應(yīng)尤其注意unless的用法，因為它表示反面條件，相當(dāng)于ifnot“如果不”、“除非”。如：Indebating,onemustcorrecttheopponent’sfacts,denytherelevanceofhisproof,ordenythatwhathepresentsasproof,ifrelevant,issufficient.(2)復(fù)合連詞aslongas，solongas，asfaras，onconditionthat，intheeventthat；動詞及分詞provided(that)，providing(that)，giventhat,suppose/supposing(that)，assuming，say等引導(dǎo)條件狀語從句。如：YoucanarriveinBeijingearlierforthemeetingprovidedyoudon’tmindtakingthenighttrain.Assumingheisdiligentinhisstudiesatordinarytimes,heissuretopassthetest.Intheeventthatshehasnotbeeninformed,Iwilltellher.(如果……)Youcangoswimmingonconditionthatyoudon’tgotoofarfromtheriverbank.(如果……)Supposeitrained,wewouldstillgo.(假如……)Sayitweretrue,whatwouldyoudoaboutit?(假如……)(3)祈使句表示條件。如：Dresswarmly,orelseyou’llcatchcold.Talktoanyoneinthedrugindustry,andyou’llsoondiscoverthatthescienceofgeneticsisthebiggestthingtohitdrugresearchsincepenicillinwasdiscovered.2.讓步狀語從句的?？贾R點(1)as引導(dǎo)讓步從句，要求用倒裝結(jié)構(gòu)，把強調(diào)的部分置于句首。如：Muchashelikesher,hedoesgetirritatedwithhersometimes.Humbleasitmaybe,thereisnoplacelikehome.(2)while引導(dǎo)讓步從句。如:Everybodycheatsalittle,somepsychologistssay,whileothersinsistthatmostpeoplearebasicallyhonestandsomewouldn’tcheatunderanycircumstances.(3)復(fù)合連接詞forallthat和分詞granting/granted(that)引導(dǎo)讓步從句。如:Grantedyouhavemademuchprogress,youshouldnotbeconceited.Forallthatcomputerscanprovideuswithgreathelp,theyshouldn’tbeseenassubstitutesforfundamentalthinkingandreasoningskills.3.時間狀語從句的?？贾R點(1)before表示漢語的“只有/必須……才能”。如:Newideassometimeshavetowaitforyearsbeforetheyarefullyaccepted.(2)when引導(dǎo)時間從句時，如果出現(xiàn)在后半句，則表示“這/那時突然”。如：IhavejuststartedbackforthehousetochangemyclotheswhenIheardthevoices.(3)whenitcomesto是習(xí)慣用法，意為“當(dāng)談到……時”。如：Doingyourhomeworkisasurewaytoimproveyourtestscores,andthisisespeciallytruewhenitcomestoclassroomtests.(4)名詞短語、介詞短語each/everytime,themoment/second/minute,inthetime,bythetime起連詞作用。如:Ihopeherhealthwillhaveimprovedgreatlybythetimewecomebacknextyear.MypainmusthavebeenapparentthemomentIwalkedintotheroom,forthefirstmanImetaskedsympathetically:“Areyoufeelingallright?”Mercury’svelocityissomuchgreaterthantheEarth’sthatitcompletesmorethanfourrevolutionsaroundtheSuninthetimeittakestheEarthtocompleteone.(5)副詞directly,immediately,instantly,now引導(dǎo)時間從句,相當(dāng)于assoonas。如:Thepolicemenwentintoactiondirectlytheyheardthealarm.4.原因狀語從句的常考知識點(1)inthat引導(dǎo)原因從句時,有時翻譯成“是因為”、“就在于”。如:Advertisingisdistinguishedfromotherformsofcommunicationinthattheadvertiserpaysforthemessagetobedelivered.Criticismandself-criticismisnecessaryinthatithelpsustofindandcorrectourmistakes.(2)nowthat表示“既然”;seeingthat,considering表示“鑒于”、“考慮到”。如:Nowthatwehaveallthematerialready,weshouldbeginthenewtaskatonce.Hedidpoorlyintheexaminations,consideringhowhardhehadtriedforthem.Seeingthatsheislawfullyoldenoughtogetmarried,Idon’tthinkyoucanstopher.其他引導(dǎo)原因狀語從句的連接詞語還有:forthe(simple)reasonthat,byreasonthat,onthegroundsthat,inasmuchas,insofaras等。5.while,whereas引導(dǎo)對比從句如:WhiletheteenagepopulationintheUnitedStateshasdeclinedoverthepastdecade,violentcrimescommittedbyjuvenileshavesharplyincreased.Ababymightshowfearofanunfamiliaradult,whereasheislikelytosmileandreachouttoanotherinfant.6.so…that…,withtheresultthat,somuchsothat引導(dǎo)結(jié)果狀語從句如:Overtheyears,alargenumberofoverseasstudentshavestudiedatthatuniversitywiththeresultthatithasacquiredsubstantialexperienceindealingwiththem.Hehimselfbelievedinfreedom,somuchsothathewouldratherdiethanlivewithoutit.7.inorderthat,incase,forfearthat,lest(用虛擬語氣)引導(dǎo)目的狀語從句如:Givemeyourtelephonenumber,incaseIneedyourhelp.HelenlistenedcarefullyinorderthatshemightdiscoverexactlywhatJohnwanted.8.where作為連接副詞的一種用法,翻譯為“在……地方”如:InJapan,aperson’scapabilitiesarenotforcedintoaninflexiblespecialty.Wherethereiswillingnessandintelligence,thereisaplacewithinthecompanytotryandtosucceed.非謂語動詞的其他考點1.接不定式或動名詞做賓語都可以，但在意思上有區(qū)別的動詞的用法meantodo想要(做某事)meandoing意味(做某事)proposetodo打算(做某事)proposedoing建議(做某事)forgettodo忘記(要做的事)forgetdoing忘記(已做的事)remembertodo記得(要做某事)rememberdoing記得(做過)goontodo繼而(做另一件事)goondoing繼續(xù)(做原來的事)stoptodo停下來去做另一件事stopdoing停止正在做的事regrettodo(對將要做的事)遺憾regretdoing(對已做過的事)后悔2.不定式的習(xí)慣用法句型：cannothelpbutdocannotbutdocannotchoosebutdocandonothingbutdohavenochoice/alternativebuttodo上述句型的意思接近，即“不得不做”、“不禁做”、“不由自主地做”、“不能不做”、“只能做”。如：Nobodycanhelpbutbefascinatedbytheworldintowhichheistakenbythesciencefiction.WhenIconsiderhowtalentedheisasapainter,Icannothelpbutbelievethatthepublicwillappreciatehisgift.3.動名詞的習(xí)慣用法句型：bebusy/activedoingsth.havedifficulty/trouble/problemdoingsth.It’snogood/use/picnicdoingsth.haveagood/great/wonderfultimedoingsth.spend/wastetimedoingsth.Thereisnopoint/sense/harm/usedoingsth.cannothelpdoingsth.Thereisnodoingsth.Iknowitisn’timportantbutIcan’thelpthinkingaboutit.Thereisnousecryingoverspiltmilk.Alicewashavingtroublecontrollingthechildrenbecausethereweresomanyofthem.4.therebe非謂語動詞的用法(1)做賓語時取決于謂語動詞的持續(xù)要求。如：Thestudentsexpectedtheretobemorereviewingclassesbeforethefinalexams.(expect要求接不定式做賓語)(2)做目的狀語或程度狀語時用fortheretobe，做其他狀語用therebeing。如：Fortheretobesuccessfulcommunication,theremustbeattentivenessandinvolvementinthediscussionitselfbyallpresent.(fortheretobe…在句中做目的狀語)Itisn’tcoldenoughfortheretobeafrosttonight,soIcanleaveJim’scaroutquitesafely.(fortheretobe…在句中做程度狀語)Therebeingnofurtherquestions,we’llstopheretoday.(therebeing…做原因狀語)(3)引導(dǎo)主語用fortheretobe。如：Itisunusualfortheretobenolatecomerstoday.(4)做除for外的介詞賓語，用therebeing。如：Hewouldalwaysignorethefactoftherebeingsuchacontradictioninhisinnerthought.定語從句中關(guān)系代詞that的用法(1)在既指人又指事物的兩個或兩個以上的先行詞后面。例如：Theyaretalkingaboutthepeopleandcountriesthattheyhadvisited.(2)在限制性定語從句中有形容詞最高級的先行詞后面。例如：HeisthebeststudentthatIhaveevermet.(3)在以“Itis...”,“Itwas...”等開頭的強調(diào)句中，和相應(yīng)的疑問句中。如：Whatisitthathewants?(4)在only,all,little的后面ThisisallthatIknow.(5)在no,every,some和any等詞后面，也包括在它們的復(fù)合詞在內(nèi)。如：Thereisnopersonthatisalwaysintheright.IsthereanythingthatIcandoforyou?近義詞辨析beautiful,goodlooking,handsome,lovely,pretty這組詞均含有“美麗”、“漂亮”、“可愛”的意思。beautiful指能不僅給人帶來感官上的快樂，而且通過感官產(chǎn)生思想和靈魂的愉悅，在同類詞中層次最高。ShewasevenmorebeautifulthanIhadremembered.她比我記憶中的她更漂亮了。goodlooking不如handsome,pretty意思強烈，指一般的“好看”或“悅目”。Thatgoodlookingyoungmanvisitedthehouseonceortwiceaweek.那個長相不錯的年輕人一星期光顧一兩次。handsome通常是一種客觀的不帶感情色彩的評價。一個人如被形容為handsome,是指此人外貌符合觀察者的要求，但不激發(fā)更深層的感受。Helookedveryhandsomeinhisdarksuit.他穿深色西裝顯得非常英俊。lovely比感官的快樂更進一步，是強調(diào)純粹情感上的愉悅，指覺得某人或某物“可愛”。Maryhastwolovelydaughters.瑪麗有兩個可愛的女兒。prettypretty也是“漂亮、可愛”的意思。很少形容大而有影響力的事物，多形容事物不以其優(yōu)秀、完美而以小巧、優(yōu)雅、精致見長，使人容易接受并喜愛。Herboyfriendbelievesthatsheistheprettiestgirlinthetown.她男朋友覺得她是鎮(zhèn)上最漂亮的女孩。關(guān)于dare的意義和用法作為情態(tài)動詞表示“膽敢”，dare通常只用于否定陳述句和疑問句。例如：Idarenotgothere.Howdarehesaysuchrudethingsaboutme?dare作為情態(tài)助動詞沒有過去式形式，其否定式為daren’t，既可指現(xiàn)在時間，也可指過去時間。例如：Tomwantedtocome,buthedaren’t.dare還可用主動詞，隨后的不定式可帶to,也可不帶to。例如：Hedoesnotdare(to)answer.Doesshedare(to)gotherealone?近義詞辨析besides,but,except,exceptfor這組詞均含有“除…外”的意思。besides“除…外，還有…”，指更進一步的擁有，包括所“除”事物在內(nèi)。Haveyougotanyclothesbesidesthese?除了這些衣服你還有別的嗎?but不包括所引事物在內(nèi)，多與nothing,notanything,nobody,nowhere,all,anybody等連用。Hehasnobodybuthimselftoblameforthat.那件事他沒法指責(zé)別人，只能怪他自己。except不包括所引事物。常與no,none,nothing等否定詞或all,everyone,everything等連用，但不可用于句首。Theyallw