外研選擇性必修第二冊(cè)Unit5Period2Grammar12ToknowtheusageofitasanemptyobjectTouseitasanemptyobjectcorrectly目標(biāo)一：ToknowtheusageofitasanemptyobjectActivity1:Lookatthesentencesandanswerthequestions.Sentence(a)and(c)arefromthereadingpassage.a.NovisitorwouldthinkitsurprisingthattheislandisaUNESCOWorldHeritageSite.b.NovisitorwouldthinkthatislandbeingaUNESCOWorldHeritageSiteissurprising.c.Expertsfeltitnecessarytocomeupwithaplantoremovealltherabbitsfromtheisland.d.Expertsfelttocomeupwithaplantoremovealltherabbitsfromtheislandwasnecessary.1Whatdoes“it”refertointhesentences(a)and(c)?“It”

insentence(a)refersto“theislandisaUNESCOWorldHeritageSite”.“It”

insentence(c)refersto“tocomeupwithaplantoremovealltherabbitsfromtheisland”2Whatisthedifferencebetweenthesentencesineachgroup?Whentheobjectofasentenceisathat-clause

(b)oraninfinitive(d),wesometimesuse“it”

asanemptyobjectandputtherealobjectlatertokeepbalance.Forexample,sentence(a)uses

“it”

astheemptyobjectof“think”,referringtotherealobject:“theislandisaUNESCOWorldHeritageSite”.Sentence(b)usesthat-clauseastheobjectof“think”.Nowlookformoresentenceswiththisstructureinthereadingpassage,andsummariseitsusesinyourownwords.1)Thisincidentmadeitclearthatrat,mouseandrabbitproblemneededsolvingonceandforall....Activity2:Readthefollowingsentencesandsummarisewhatcanbeuseditasanemptyobject.1

Theyfeltitdifficulttofinishtheworkinsuchashorttime.2Hethoughtitabsolutelysenselessattemptingtheimpossible.3Itookitforgrantedthattheywouldnotcome.Summary:我發(fā)現(xiàn)，可以用it作形式賓語替代的成分有：______________，______________，______________。不定式動(dòng)名詞從句當(dāng)不定式、動(dòng)名詞或從句在某個(gè)句子中做賓語時(shí)，為了保持句子的結(jié)構(gòu)平衡，常用it作為形式賓語，而將真正的賓語放到句子的后部去。【語法精講】1it作為形式賓語可以分為兩種情況：(1)代表不定式。例如：

Idon’tfeelitdifficulttounderstandthepassage.(2)代表連接代詞或連接副詞引導(dǎo)的從句或動(dòng)名詞。例如：Hehasn’tmadeitclearwhenheiscomingback.Theprofessorconsidersitnogoodreadingwithoutunderstanding.2幾種特殊情況1）動(dòng)詞+it+that從句，常見于take，have，put等動(dòng)詞之后。例如：Itakeitthathewillfinishthetaskbyhimself.（我認(rèn)為他能自己完成這項(xiàng)任務(wù)。）2）動(dòng)詞+it+when/if從句，常見于appreciate，enjoy，like，prefer等詞之后。例如：Wereallyappreciateitifyoucoulddousafavour.（如果您能幫助我，我們會(huì)很感激。）3）動(dòng)詞+it+介詞短語+that從句，常見于oweittosb，takeitforgranted等結(jié)構(gòu)中。例如：Weoweittoyouthatwearestillalive.（多有你，我們現(xiàn)在才仍然活著。）4）動(dòng)詞+介詞+it+that從句，常見于lookto，dependon，insiston，stickto，answerfor等結(jié)構(gòu)中。例如：Sheinsistedonitthatshewasinnocent.（她堅(jiān)持說自己是無辜的。）5）動(dòng)詞+it+過去分詞+從句。例如：Hemadeitknowntoeveryonethathewasright.（他讓每個(gè)人都明白他是對(duì)的。）目標(biāo)二:TouseitasanemptyobjectcorrectlyActivity1:Rewritetheunderlinedpartsusingitasanemptyobject.Thered-earedslider,aspeciesoffreshwaterturtle,isnativetotheSouthernUnitedStatesandNorthernMexico.Duetoitscuteappearance,manypeoplethinkkeepingthisturtleasapetisagoodidea.Recentyearshaveseenmoreandmorepetslidersescapingorbeingreleasedfromhomes,andsomeownersbelievetoreleasethemintothewildisnobigissue.Thesedays,peoplehavefoundtoreleasetheseturtlesintothewildisathreattootherspecies.Expertsconsiderownerskeepingtheirpetsinanenclosedareaimportant,andanyoneunabletokeeptheir

petsshouldtakethemtoan

appropriateanimalshelter.1manypeoplethinkkeepingthisturtleasapetisagoodidea2believetoreleasethemintothewildisnobigissue3peoplehavefoundtoreleasetheseturtlesintothewildisathreattootherspecies4Expertsconsiderownerskeepingtheirpetsinanenclosedareaimportant.manypeoplethinkitagoodideatokeepthisturtleasapetbelieveitnobigissuetoreleasethemintothewildpeoplehavefounditathreattootherspeciestoreleasetheseturtlesintothewildExpertsconsideritimportantforownerstokeeptheirpetsinanenclosedarea.Activity2:LookatthepicturesoftheSaihanbaNationalForestParkanddescribeitschangesusingitasanemptyobjectwhereappropriate.Youmayrefertothewordsandexpressionsinthetableforhelp.1960spresentdaynouns/adjectivestodo/thatbreakthroughimpossiblelikelyunrealistic…growinvestigateplanttreestransform…Ithinkitabreakthroughtotransformadesertintoaforest...Ibelieveitlikelythatmorevolunteerswillhelpplantmoretreesaroundthepark.Ifinditimpossibletoinvestigateallthelivingspeciesintheparkatpresent.Ifeelitunrealisticforthelocalpeopletogrowriceandwheatforgrainind