精选优质文档-倾情为你奉上一、 简单句中含有be动词、情态动词和助动词时，变否定句时需在be动词、情态动词和助动词后加not。1. （am, is ,are 是be动词）如： I am a teacherI am not a teacher This is a pen. This is not a pen.或This isnt a pen. (is not =isnt) You are a boy. You are not a boy. (are not =arent)2. （can是情态动词） He can help meHe can not help me或He cant help me.(can not =cant ) 3.当主语是第一人称、第二人称和第三人称复数时用助动词do,变否定时，在do后面加not 如：I like English .I do not like English.或I dont like English. They go to school together. They do not (
