肯定句变否定句

肯定 否定 一 动词一 动词 be 的否定式的否定式 动词 be 根据不同的人称和时态可以有 am is are was were 等不同形式 可用 作连系动词 表示 是 在 等 和助动词 用于构成进行时态和被动语态等 但不管何种情况 构成否定式时 一律在其后加 not 1 I m old but you re young I m not old but you re not young 2 He was reading and I was writing He was not reading and I was not writing 二 二 动词动词 have 的否定式的否定式 动词 have 根据不同的人称和时态可以有 have has had 等形式 可以用作实意 动词和助动词 分以下情况讨论 1 用作实意动词表示状态 如表示拥有 患病或用于 have to 表示 必须 等 在构成否定式时可以直接在其后加 not 也可根据情况在其前使用 don t doesn t didn t 1 He has a car He hasn t a car He doesn t have a car 2 He had some dictionaries He hadn t any dictionaries He didn t have any dictionaries 3 You have to go with him You haven t to go with him You don t have to go with him 注 have to 构成否定式时以在其前加 don t 等较为常见 2 用作实意动词表示动作 如表示 吃 eat 喝 drink 拿 take 收到 receive 度过 spend 等 构成否定式时不能直接在其后加 not 而应根据情况在其前使用 don t doesn t didn t 1 He had some cake for breakfast He didn t have any cake for breakfast 2 We had a good holiday We didn t have a good holiday 3 用作助动词构成完成时态 其否定式只能在其后加 not 1 I have read the book I have not read the book 2 He had left when I arrived He hadn t left when I arrived 三 情态动词的否定式三 情态动词的否定式 情态动词的否定式一般在其后加 not 构成 1 I can finish the work in an hour I can t finish the work in an hour 2 You must go with us You mustn t go with us 3 We should help them We shouldn t help them 四 实意动词的否定式四 实意动词的否定式 一般实意动词的否定式 通常应根据不同时态和人称在实意动词之前加 don t doesn t didn t 等 1 He works in a bank He doesn t work in a bank 2 We often hear from her We don t often hear from her 3 I met her at the station I didn t meet her at the station 注意 加上 does not 或 did not 改为否定句以后 要把原句的动词改为原形动词 特别 是行为动词 do 的第三人称单数 does 和过去时 did 在主语后面加上 doesn t 或 didn t 以后 千万要注意把句中的 does 或 did 改为 do 五 祈使句的否定结构为 五 祈使句的否定结构为 don t 十原形动词十原形动词 改为否定句时 要在句首加上 don t 其它不变 即 Look out of the window Don t look out of the window 6 当陈述句中含有当陈述句中含有 something 这个词时这个词时 把句子改为否定句有两种方法 其一 在句中相应位置加 not 再把 something 改成 anything 其二 直接把 something 改为 nothing 即可 1 There is something wrong with the radio 把这个句子改为否定句有两种方法 其一 先把 not 加在 is 后面 再把 something 改为 anything 即 There is not anything wrong with the radio 其二把 something 直接改为 nothing 即 There is nothing wrong with the radio 2 I have something important to tell you 把这个句子变成否定句有两种方法 其中一种方法是先把 not 加在 have 后面 再把 something 变成 anything 即 I have not anything important to tell you 第二种方法是直接把 something 改为 nothing 即 I have nothing important to tell you 7 当陈述句是一个主从复合句当陈述句是一个主从复合句 而主句的谓语动词是 think 或 believe 等时 把这种句子改为否定句 往往是否 定 think 或 believe 等而不否定后面从句中的谓语动词 尽管意思是否定从句的 谓语动词 1 I think he will be back soon 这个复合句中主句的谓语动词是 think 所以在改为否定句时要在 think 前面加 上 don t 即 I don t think he will be back soon 汉语意思 我认为他不会很快 回来 8 某些特殊句型改为否定句时 有不同的方法 某些特殊句型改为否定句时 有不同的方法 1 在陈述句中含有 had better 时 要把 not 加在 better 后面 动词原形前面 1 You had better go with us 把这个句子改为否定句 要把 not 加在 better 之后 g o 之前 即 You had better not go with us 千万不要改成 You had not better to go with us 或 You had better don t go with us 因为 要否定的是后面的动词不定式短语 同时 had better 后面要用动词原形 不带 to 2 当陈述句中含有 both 名词或者 both of 名词作主语时 改为否定句时则 用 neither 代替 both 并且要注意谓语动词数的变化 1 Both of them work in the school library 句子含有 both 改为否定句时用 neither 代替 both 同时谓语动词 work 改为 works 即 Neither of them works in the school library 2 Both answers are right 把这个句子改为否定句 用 neither 代替 both 谓语动词 are 改为 is 即 Neither answer is right 3 句中含有 both and 的肯定句改为否定句时用 neither nor 改写 同 时 neither nor 还可以把两个简单句的否定形式连成一个句子 1 Both Mary and Joan are students 把这个句子改为否定句时 通常用 Neither nor 代替 Both and 同时把 are 改为 is students 改为 a student 即 Neither Mary nor Joan is a student 4 neither nor 连接两个主语时 谓语动词决定于 nor 后面的名词或代词的 单复数形式 1 This book is both interesting and instructive 把这个句子改为否定句 用 neither nor 代替 both and 因为连接部分在 句中作表语 所以谓语动词不变 即 This book is neither interesting nor instructive 2 I don t see that film He doesn t see it either 这两个否定句可以用 neither nor 连成一个句子 谓语动词改为肯定式 see 人称和数由 nor 后面的 he 决定 即 Neither he nor I see that film 或者把 I 和 he 交换 即 Neither I nor he sees that film 这说明谓语的人称和数由 nor 后 面的靠近谓语的人称和数决定 在把肯定句改为否定句时 注意把句中的 some 改成 any 巩固练习 将下列句子改为否定句 1 We do morning exercises every day We morning exercises every day 2 All of us can swim can swim Joan I in Class One 4 There is something wrong with my bike There wrong with my bike 5 You may stay here before I come back You here before I come back 6 Read the text after me the text after me 7 Li Lei needs some help with his English Li Lei help with his English 8 He said he would g o to Beijing the next week He go to Beijing the next week 9 The bike has already been m ended The bike mended 10 I think it is going to rain tomorrow I going to rain tomorrow Key 1 don t do 2 None of us 3 Neither nor am 4 is nothing 5 mustn t stay 6 Don t read 7 doesn t need any 8 didn