英语新教材人教版九年级上册 单元语法练习 it做形式主语单项选择题练习题（教师版）

it做形式主语单项选择题练习题（教师版）一、单项选择题（50道）Itis______forustofinishourhomeworkontime.

A.important B.importantly C.importance D.unimportantly

答案：A解析：itis+形容词+forsb.todosth.结构，此处需用形容词，important（重要的）符合句意；B、D是副词，C是名词，均不符合语法。Itiskind______youtohelptheoldmancrossthestreet.

A.for B.of C.to D.with

答案：B解析：形容词kind（善良的）描述人的品质，需用介词of，构成itis+形容词+ofsb.todosth.结构；for用于修饰“事情”的形容词后。Itisdifficult______himtosolvethismathproblem.

A.of B.to C.for D.with

答案：C解析：形容词difficult（困难的）描述“解决数学题”这件事，需用介词for，构成itis+形容词+forsb.todosth.结构，固定搭配。Itis______tolearnaforeignlanguagewellinashorttime.

A.possible B.possibly C.impossible D.impossibly

答案：C解析：itis+形容词+todosth.结构，需用形容词；结合句意，短时间内学好外语是“不可能的”，impossible（不可能的）符合，A不符合常识，B、D是副词。______isnecessaryforeveryonetokeephealthy.

A.This B.That C.It D.He

答案：C解析：此处需用it作形式主语，替代后面的不定式短语tokeephealthy，固定句式itis+形容词+forsb.todosth.，其他选项不能作形式主语。Itisagoodidea______awalkafterdinner.

A.take B.totake C.taking D.takes

答案：B解析：itis+名词短语+todosth.结构，真正主语是不定式totakeawalk，固定搭配，其他选项不符合语法。Itissaid______hewillcometoourschoolnextweek.

A.that B.which C.what D.who

答案：A解析：itissaidthat...是固定句式，it作形式主语，that引导真正主语从句，无实际含义，不可省略，其他选项不能引导此类从句。It______thatshemissedthebusthismorning.

A.happen B.happens C.happened D.happening

答案：C解析：ithappensthat...表示“碰巧……”，thismorning提示用一般过去时，happen的过去式是happened，A是原形，B是第三人称单数，D是现在分词，均不符合时态。Itdoesn’tmatter______youarelateornot.

A.that B.if C.whether D.what

答案：C解析：itdoesn’tmatterwhether...ornot是固定搭配，whether表“是否”，可与ornot连用；if不能与ornot连用，that、what不符合句意。Itisclear______heisgoodatEnglish.

A.that B.where C.when D.how

答案：A解析：itis+形容词+that从句结构，it作形式主语，that引导真正主语从句，从句语义完整，用that连接，其他选项引导的从句语义不完整。Itisnouse______aboutthebadweather.

A.complain B.complaining C.tocomplain D.complained

答案：B解析：itisnousedoingsth.是固定搭配，it作形式主语，真正主语是动名词complaining，意为“做某事没用”，其他选项不符合固定结构。Itis______ofyoutogiveupyourseattothekid.

A.polite B.politely C.impolite D.impolitely

答案：A解析：itis+形容词+ofsb.todosth.结构，需用形容词；结合句意，给小孩让座是“有礼貌的”，polite（礼貌的）符合，C（不礼貌的）语义相反，B、D是副词。Itisessential______ustolearnbasiccomputerskills.

A.of B.for C.with D.to

答案：B解析：形容词essential（必不可少的）描述“学习电脑技能”这件事，需用介词for，构成itis+形容词+forsb.todosth.结构，固定搭配。______isimpossibleforastudenttoknoweverything.

A.This B.That C.It D.There

答案：C解析：固定句式itis+形容词+forsb.todosth.，it作形式主语，替代后面的不定式短语，其他选项不能作形式主语，Therebe句型表“存在”，不符合句意。Itissurprising______hepassedthedifficultexam.

A.that B.if C.whether D.how

答案：A解析：itis+形容词（surprising）+that从句结构，it作形式主语，that引导真正主语从句，从句语义完整，无需其他疑问词，故选A。Itiswise______hertoasktheteacherforhelp.

A.for B.of C.to D.with

答案：B解析：形容词wise（明智的）描述人的品质，需用介词of，构成itis+形容词+ofsb.todosth.结构，区别于修饰“事情”的forsb.。Itisdangerous______aloneatnight.

A.goout B.goingout C.togoout D.wentout

答案：C解析：itis+形容词+todosth.结构，真正主语是不定式togoout，it作形式主语，其他选项不符合语法（A是原形，B是动名词，D是过去式）。Itisreported______thecitywillholdasportsmeetingnextyear.

A.that B.what C.which D.who

答案：A解析：itisreportedthat...是固定句式，it作形式主语，that引导真正主语从句，表“据报道……”，其他选项不能引导此类从句。It______tomethatIleftmykeysathome.

A.occur B.occurs C.occurred D.occurring

答案：C解析：itoccurstosb.that...表示“某人突然想到……”，结合句意，“想到忘带钥匙”是过去发生的事，用一般过去时，occur的过去式是occurred。Itisnecessarythatwe______hardeveryday.

A.study B.studies C.studied D.studying

答案：A解析：itisnecessarythat...结构中，that从句需用虚拟语气（should+动词原形），should可省略，故用study（动词原形）。Itisnogood______toomuchtimeplayinggames.

A.spend B.spending C.tospend D.spent

答案：B解析：itisnogooddoingsth.是固定搭配，it作形式主语，真正主语是动名词spending，意为“做某事没好处”，其他选项不符合固定结构。Itiskind______himtohelpmewithmyhomework.

A.for B.of C.at D.in

答案：B解析：形容词kind（善良的）描述人的品质，需用介词of，构成itis+形容词+ofsb.todosth.结构，固定搭配，其他介词不符合。Itisdifficult______finishtheworkintwodays.

A.forweto B.forusto C.ofusto D.ofweto

答案：B解析：itis+形容词+forsb.todosth.结构，for后接宾格us（we的宾格），difficult修饰“完成工作”这件事，用for，A中we是主格，C、D介词错误。Itisobvious______hedidn’ttellthetruth.

A.that B.which C.what D.when

答案：A解析：itis+形容词（obvious，明显的）+that从句结构，it作形式主语，that引导真正主语从句，从句语义完整，无需其他疑问词。______isusefultolearnasecondlanguage.

A.This B.That C.It D.He

答案：C解析：固定句式itis+形容词+todosth.，it作形式主语，替代后面的不定式短语tolearnasecondlanguage，其他选项不能作形式主语。Itisstrange______shedidn’tcometoschooltoday.

A.that B.if C.whether D.where

答案：A解析：itis+形容词（strange，奇怪的）+that从句结构，it作形式主语，that引导真正主语从句，从句语义完整，if、whether表“是否”，where表“哪里”，均不符合句意。Itisadvisablethatwe______earlytomorrowmorning.

A.leave B.leaves C.left D.leaving

答案：A解析：itisadvisablethat...结构中，advisable（明智的）表建议，that从句需用虚拟语气（should+动词原形），should可省略，故用leave。Itisharmful______ustosmoke.

A.for B.of C.to D.with

答案：A解析：形容词harmful（有害的）描述“吸烟”这件事，需用介词for，构成itis+形容词+forsb.todosth.结构，固定搭配，其他介词不符合。Itissaidthat______willraintomorrow.

A.this B.that C.it D.he

答案：C解析：此处it是真实主语，指代天气，固定表达“itwillrain”（将要下雨）；前面的it是形式主语，替代that从句，注意区分形式主语和真实主语。IthappenedthatI______myoldfriendinthepark.

A.meet B.meets C.met D.meeting

答案：C解析：ithappenedthat...中，happened是过去式，从句需用对应过去时，meet的过去式是met，A是原形，B是第三人称单数，D是现在分词，均不符合时态。Itisimportant______weshouldprotecttheenvironment.

A.that B.if C.whether D.what

答案：A解析：itisimportantthat...结构，it作形式主语，that引导真正主语从句，从句中should可省略，其他选项不能引导此类从句，不符合句意。Itisuseless______topersuadehimtochangehismind.

A.try B.trying C.totry D.tried

答案：B解析：itisuselessdoingsth.是固定搭配，it作形式主语，真正主语是动名词trying，意为“做某事无用”，区别于itis+形容词+todosth.结构。Itispolite______youtosay“thankyou”whenyougethelp.

A.for B.of C.to D.at

答案：B解析：形容词polite（有礼貌的）描述人的品质，需用介词of，构成itis+形容词+ofsb.todosth.结构，固定搭配。Itiseasy______himtoplaythepiano.

A.of B.for C.with D.in

答案：B解析：形容词easy（容易的）描述“弹钢琴”这件事，需用介词for，构成itis+形容词+forsb.todosth.结构，固定搭配。Itisclear______sheisthebeststudentinourclass.

A.that B.who C.what D.where

答案：A解析：itis+形容词（clear，明显的）+that从句结构，it作形式主语，that引导真正主语从句，从句语义完整，无需其他疑问词。______isapitythatyoumissedtheconcert.

A.This B.That C.It D.There

答案：C解析：itisapitythat...是固定句式，it作形式主语，替代后面的that从句，表“……真是遗憾”，其他选项不能作形式主语。Itisreported______manystudentswilltakepartinthecompetition.

A.that B.which C.what D.who

答案：A解析：itisreportedthat...是固定句式，it作形式主语，that引导真正主语从句，表“据报道……”，其他选项不能引导此类从句。Itdoesn’tmatter______youtakethebusorwalk.

A.that B.if C.whether D.how

答案：C解析：itdoesn’tmatterwhether...ornot是固定搭配，whether表“是否”，可与or（ornot）连用；if不能与or连用，that、how不符合句意。Itisgood______everymorning.

A.exercise B.exercising C.toexercise D.exercised

答案：C解析：itis+形容词+todosth.结构，真正主语是不定式toexercise，it作形式主语，表“每天早上锻炼是好的”；A是名词，B是动名词，D是过去式，均不符合语法。Itisfoolish______himtomakesuchamistake.

A.for B.of C.to D.with

答案：B解析：形容词foolish（愚蠢的）描述人的品质，需用介词of，构成itis+形容词+ofsb.todosth.结构，固定搭配。Itisimpossible______ustofinishtheworkaheadoftime.

A.of B.for C.with D.to

答案：B解析：形容词impossible（不可能的）描述“提前完成工作”这件事，需用介词for，构成itis+形容词+forsb.todosth.结构，固定搭配。Itisbelieved______theearthgoesaroundthesun.

A.that B.what C.which D.who

答案：A解析：itisbelievedthat...是固定句式，it作形式主语，that引导真正主语从句，表“人们相信……”，从句是客观事实，用一般现在时。Itisessentialthatwe______carefulinclass.

A.be B.is C.are D.was

答案：A解析：itisessentialthat...结构中，essential（至关重要的）表必要，that从句需用虚拟语气（should+动词原形），should可省略，be是动词原形，符合要求。Itisnouse______aboutthepast.

A.worry B.worrying C.toworry D.worried

答案：B解析：itisnousedoingsth.是固定搭配，it作形式主语，真正主语是动名词worrying，意为“担心过去是没用的”，其他选项不符合固定结构。Itiskind______youtoinvitemetoyourbirthdayparty.

A.for B.of C.at D.in

答案：B解析：形容词kind（善良的）描述人的品质，需用介词of，构成itis+形容词+ofsb.todosth.结构，固定搭配，其他介词不符合。Itisdifficult______solvethisprobl