小学英语句型转换之肯定句变否定句经典.ppt

zx zx zx zx zx zx zx zx 小学英语句型转换 ——肯定句变否定句 .,., * 一、概念：什么是肯定句和否定句？ ｛ 肯定形式→肯定句 否定形式→否定句 陈述句 陈述句：说明一件事情、一个想法，提出一个观点或表达自己心情的句子。特点是：句末都是句号，用降调读！ .,., 肯定句变否定句的方法 1.含“be动词和情态动词”型，直接在be动词或情态动词后加not,其它照抄不变。 be动词包括：am,is,are,was,were. 常见的情态动词有：can,could,would,will,may等等。 例句：I am a student. → I am not a student. → → He is a boy. He is not/isnt a boy. I can speak English. I can not/cant speak English. .,., * 肯定句变否定句的方法 注意缩写： is not = isnt, are not = arent , was not = wasnt, were not = werent, am not没有缩写， 但是I am = Im can not = cant, would not = wouldnt could not = couldnt, will not = wont .,., 肯定句变否定句的方法 2.含“实意动词”型，转换否定句时，记住五个字“一加一还原”的原则。“一加”即在实意动词前加助动词的否定dont,doesnt或didnt。“一还原”即把句中的实意动词变回原形。 注意：在一般现在时中，当主语是第一、二人称或复数时，加dont来否定；当主语是第三人称或单数时，加doesnt来否定； 在一般过去时中，一律用didnt来否定。 例句：I like apples. → → → I dont like apples. He likes apples. He doesnt like apples. She worked last night. She didnt work last night. .,., 肯定句变否定句的方法 要注意的特殊情况： 遇到some 变 any; 遇到too/also变either; 遇到and 变 or; 遇到always 变 never。 例句:1.There are some boys in the classroom. There arent any boys in the classroom. 2.The girl can sing and dance. The girl cant sing or dance. .,., zx zx zx zx zx zx zx zx zx