小升初英语语法专项提高训练陈述句改为否定句

在英语学习的旅程中，陈述句的否定形式是我们表达相反意义、提出不同看法时不可或缺的工具。对于即将面临小升初的同学们而言，熟练掌握陈述句改否定句的规则，不仅能提升语法应用能力，更能在各类考试中从容应对。本文将系统梳理这一知识点，结合实例进行讲解，并辅以针对性练习，帮助同学们扎实掌握，灵活运用。一、认识陈述句与否定句首先，我们要明确什么是陈述句。陈述句是用来陈述一个事实、表达一种看法或描述一种状态的句子，句末通常用句号。例如："Shelikesapples."（她喜欢苹果。）或"Theyareplayingfootball."（他们正在踢足球。）而否定句，则是在陈述句的基础上，通过添加否定词，表达与原句相反的意义。例如："Shedoesnotlikeapples."（她不喜欢苹果。）或"Theyarenotplayingfootball."（他们没有在踢足球。）二、陈述句改否定句的基本规则与实例解析将陈述句改为否定句，关键在于根据原句中谓语动词的特点，选择正确的否定方式。我们可以按照谓语动词的类型来分类学习：（一）句中含有be动词（am,is,are,was,were）的情况规则：直接在be动词后面加"not"。*肯定句结构：主语+be动词+其他成分.*否定句结构：主语+be动词+not+其他成分.例句解析：1.肯定句：Iamastudent.（我是一名学生。）否定句：Iamnotastudent.（我不是一名学生。）*解析：直接在am后加not。2.肯定句：Heishappytoday.（他今天很高兴。）否定句：Heisnothappytoday./Heisn'thappytoday.（他今天不高兴。）*解析：在is后加not，可缩写为isn't。3.肯定句：Theyareplayinginthepark.（他们正在公园里玩。）否定句：Theyarenotplayinginthepark./Theyaren'tplayinginthepark.（他们没在公园里玩。）*解析：在are后加not，可缩写为aren't。4.肯定句：Thebookwasonthedeskyesterday.（昨天书在桌子上。）否定句：Thebookwasnotonthedeskyesterday./Thebookwasn'tonthedeskyesterday.（昨天书没在桌子上。）*解析：在was后加not，可缩写为wasn't。（二）句中含有情态动词（can,may,must,should,will,would等）的情况规则：直接在情态动词后面加"not"。*肯定句结构：主语+情态动词+动词原形+其他成分.*否定句结构：主语+情态动词+not+动词原形+其他成分.例句解析：1.肯定句：Icanswim.（我会游泳。）否定句：Icannotswim./Ican'tswim.（我不会游泳。）*解析：在情态动词can后加not，可缩写为can't。2.肯定句：Youmustfinishyourhomeworkfirst.（你必须先完成作业。）否定句：Youmustnotfinishyourhomeworkfirst./Youmustn'tfinishyourhomeworkfirst.（你不许先完成作业。）[注：mustnot表示“禁止”，语气较强。“不必”常用neednot/don'thaveto]*解析：在情态动词must后加not，可缩写为mustn't。3.肯定句：ShewillgotoBeijingtomorrow.（她明天要去北京。）否定句：ShewillnotgotoBeijingtomorrow./Shewon'tgotoBeijingtomorrow.（她明天不去北京。）*解析：在情态动词will后加not，可缩写为won't。（三）句中含有实义动词（行为动词）的情况当陈述句的谓语是实义动词（如like,eat,play,run等）时，改为否定句需要借助助动词"do"、"does"或"did"，并在其后加"not"，原来的实义动词用原形。1.一般现在时：*规则：主语是第三人称单数（he,she,it,单数名词或不可数名词）时，用"doesnot"(doesn't)+动词原形；其他人称（I,you,we,they,复数名词）用"donot"(don't)+动词原形。*肯定句结构：主语+动词原形/动词第三人称单数形式+其他成分.*否定句结构：主语+don't/doesn't+动词原形+其他成分.例句解析：*肯定句：Ilikebananas.（我喜欢香蕉。）否定句：Idonotlikebananas./Idon'tlikebananas.（我不喜欢香蕉。）*解析：主语是I，非第三人称单数，用don't+动词原形like。*肯定句：Heplaysbasketballeveryafternoon.（他每天下午打篮球。）否定句：Hedoesnotplaybasketballeveryafternoon./Hedoesn'tplaybasketballeveryafternoon.（他不是每天下午都打篮球。）*解析：主语是he，第三人称单数，用doesn't+动词原形play（原句中的plays变回原形play）。2.一般过去时：*规则：无论主语是谁，均用"didnot"(didn't)+动词原形。*肯定句结构：主语+动词过去式+其他成分.*否定句结构：主语+didn't+动词原形+其他成分.例句解析：*肯定句：TheywenttotheparklastSunday.（他们上周日去了公园。）否定句：TheydidnotgototheparklastSunday./Theydidn'tgototheparklastSunday.（他们上周日没去公园。）*解析：一般过去时，用didn't+动词原形go（原句中的went变回原形go）。*肯定句：ShewatchedTVyesterdayevening.（她昨晚看了电视。）否定句：ShedidnotwatchTVyesterdayevening./Shedidn'twatchTVyesterdayevening.（她昨晚没看电视。）*解析：一般过去时，用didn't+动词原形watch（原句中的watched变回原形watch）。三、特殊情况与注意事项1.some和any的转换：在肯定句中表示“一些”时常用"some"，但在否定句中通常要改为"any"。*例句：Therearesomebooksonthedesk.→Therearenotanybooksonthedesk./Therearen'tanybooksonthedesk.（桌子上没有书。）*（也可以说：Therearenobooksonthedesk."no"=notany）2.and和or的转换：在肯定句中连接并列成分常用"and"，在否定句中连接并列成分常用"or"。*例句：Ilikecoffeeandtea.→Idon'tlikecoffeeortea.（我不喜欢咖啡也不喜欢茶。）3.含有"have/has"的句子：*当"have/has"表示“拥有”时，英式英语中可以直接在其后加"not"(haven't/hasn't)，也可以用"donothave"(don'thave)/"doesnothave"(doesn'thave)。美式英语更倾向于后者。*例句：Shehasanewbike.→Shehasn'tanewbike.(BrE)/Shedoesn'thaveanewbike.(AmE/BrE)（她没有新自行车。）*当"have/has"作为助动词构成完成时态时，则直接在其后加"not"(haven't/hasn't)。*例句：Theyhavefinishedtheirwork.→Theyhavenotfinishedtheirwork./Theyhaven'tfinishedtheirwork.（他们还没完成工作。）四、专项练习请将下列陈述句改为否定句：1.Tomisagoodstudent.2.TheycanspeakChinese.3.Weplayfootballafterschool.4.Mymothercooksdinnereveryday.5.Iwentshoppingwithmyfriendyesterday.6.Thereissomemilkintheglass.7.Helikessinginganddancing.8.Shehasareddress.参考答案：1.Tomisnotagoodstudent./Tomisn'tagoodstudent.2.TheycannotspeakChinese./Theycan'tspeakChinese.3.Wedonotplayfootballafterschool./Wedon'tplayfootballafterschool.4.Mymotherdoesnotcookdinnereveryday./Mymotherdoesn'tcookdinnereveryday.5.Ididnotgoshoppingwithmyfriendyesterday./Ididn'tgoshoppingwithmyfriendyesterday.6.Thereisnotanymilkintheglass./Thereisn'tanymilkintheglass.(或Thereisnomilkintheglass.)7.Hedoesnotlikesingingordancing./Hedoesn'tlikesingingordancing.8.Shedoesnothaveareddress./Shedoesn'thaveareddress.(或Shehasn'tareddress.-英