it is用法

1、ItItisis......thatsincebefethatsincebefe等句型歸納等句型歸納1.1.為了突出或強調(diào)句中的某一成分以加強語氣為了突出或強調(diào)句中的某一成分以加強語氣英語中通常用英語中通常用“It“Itisis被強調(diào)成分被強調(diào)成分thatwho”thatwho”結(jié)構(gòu)，這一結(jié)構(gòu)叫作結(jié)構(gòu)，這一結(jié)構(gòu)叫作強調(diào)結(jié)構(gòu)強調(diào)結(jié)構(gòu)。該。該結(jié)構(gòu)中的結(jié)構(gòu)中的ItIt是無人崐是無人崐稱主語稱主語沒有詞匯意義沒有詞匯意義僅起到改變句子結(jié)僅起到改

2、變句子結(jié)構(gòu)使某一成分受到強調(diào)的作用。如被崐使某一成分受到強調(diào)的作用。如被崐強調(diào)的是物，用強調(diào)的是物，用thatthat如被強調(diào)的是人被強調(diào)的是人用whowho也可用也可用thatthat。強調(diào)結(jié)構(gòu)中被強調(diào)的成分通常是句中的主語、賓語、地點狀語或時間狀語。例如下面一句我們可分別對其不同成分進行強調(diào)：Johnweawhitesuitatthedancelastnight.1.ItwasJohnthatwhoweawhitesuitatthe

3、dancelastnight.（強調(diào)主語）2.ItwasawhitesuitthatJohnweatthedancelastnight.(強調(diào)賓語）3.ItwasatthedancethatJohnweawhitesuitlastnight.(強調(diào)地點狀語）4.ItwaslastnightthatJohnweawhitesuitatthedance.（強調(diào)時間狀語）強調(diào)結(jié)構(gòu)亦可用來強調(diào)某些狀語從句：Itwasbecausehewasil

4、lthathedidntcometoschoolyesterday.（強調(diào)because引導(dǎo)的原因狀語從句）Itwasonlywhenthewarwasoverin1949thathewasabletogetbackhome.(強調(diào)when引導(dǎo)的時間狀語從句）Itwasnotuntilhisfathercamebackthathewenttobed.(強調(diào)until引導(dǎo)的時間狀語從句）現(xiàn)談?wù)剰娬{(diào)結(jié)構(gòu)中值得注意的幾個問題：一.強調(diào)結(jié)構(gòu)中的

5、時態(tài)問題強調(diào)結(jié)構(gòu)中的時態(tài)問題如果被強調(diào)的成分，原句謂語動詞是一般現(xiàn)在時或一般將來時，強調(diào)結(jié)構(gòu)用Itis...thatwho如果原句的謂語動詞是過去時態(tài)，則用Itwas...thatwho有時還可用be的其它形式。例如：Itisthepeoplewhothatarereallypowerful.ItwasinthestreetthatImetyourbrotheryesterday.Itmustbeyourmotherwhoyouaret

6、hinkingof.二.強調(diào)結(jié)構(gòu)中代詞的格和謂語人稱與數(shù)的問題如果被強調(diào)的部分是原句的主語thatwho后面的謂語在人稱和數(shù)上均應(yīng)與原句主語一致不與it一致。例如：Itisyouthatwhoaretoblame.Itisawonderthatherefusedsuchagoodoffer.Itiscommonknowledgethatthetrafficsituationthereisdeplable.用于該句型的名詞常見有：comm

7、onknowledgecommonsenseagoodthinganhonamercyapityapleasureashameasurpriseawonder等。4Itisadj.that…該句型為主語從句。It為形式主語，真正的主語也是由that引導(dǎo)的從句。例如：Itiscertainthatweshallbelate.It’sstrangethathedidn’tcomeyesterday.Isn’titstrangethatthe

8、lazyboy(should)passtheexam.能用于該句型的形容詞常見的有：certainclearcuriousdisappointingdreadfulfitftunatefrighteningfunnygoodimptantluckynaturalnecessaryobviouspeculiarpleasingpossibleprobableproperrightsadsurprisingremarkableunftuna

9、teunimptantunnecessaryunusualuselesswellwonderfulwrongtrue等。that從句可用陳述語氣，也可用should動詞原型的虛擬語氣形式。用陳述語氣表示客觀事實；用虛擬語氣表示驚訝、喜悅、遺憾、失望等感情色彩或表示要求、建議、命令、愿望等。5Itisp.p.that…該句型為主語從句。It為形式主語，真正的主語是that引導(dǎo)的從句。例如：ItwassaidthatMr.Whitehadb

10、eenwritinganewTVplay.Itisreptedthatthesptsmeethasbeenputoff.Ithasnotbeendecidedthatwhenwhereweillholdthemeeting.能用于該句型的過去分詞常見的有：admittedannouncedbelieveddecideddemeddisclosedexpectedfoundhopedreptedrequestedsaidseensugge

11、stedthoughttoldunknown等。6Itis…befe…該句型的is后可接long或一段時間?？隙ň渥g為“過多久…才…”；否定句譯為“沒多久…就…”。例如：ItwasalongtimebefeIgottosleepagain.Itwillbehoursbefehearriveshere.Itwasnotlongbefehelefthishometown.Itwillbefiveyearsbefewemeetagain.It

12、wasn’tlongbefehetoldusaboutthisaffair.Itwaseveningbefewereachedthelittletown.7Itis…since…該句型表達“從……以來已經(jīng)多久了”的意思。這一結(jié)構(gòu)多用一般過去時，表示從過去某一時刻起到說話這一時刻止的這段時間的總和。時間的起點，無論是那種動詞，一律從since從句中的謂語動詞表示的動作的完成的那一刻算起。例如：Itis15yearssincetheware