not和isn't的区别怎么用

not和isn't的区别怎么用？

not 是否定副词，不能单独使用

isn't 是be动词和否定副词的缩写，释义:不是

如:He isn't a teacher.

The glass isn't broken by me.

My sister isn't at school.

not否定动词，要看动词是什么动词。

1 动词在句中作谓语，有三种语气——陈述语气、虚拟语气和祈使语气。

1）祈使语气：否定动词时在动词原型前加do not 或 don't。例如：

Don't move.

Don't be stupid.

2) 动词原型式虚拟语气：否定动词时直接在动词原型前加not。例如：

I suggested that he not come the next day.

3) 陈述语气：not否定陈述语气谓语动词必须借助操作词（能和not构成缩合形式的24个限定动词形式，如isn't, shouldn't, won't中的is，should, will等）not加在操作词之后。如果一个句子中没有操作词，就必须加操作词do, does 或did 之一，然后加not (实意动词改为不带to的不定式）。例如：

He is not at home. (原句有操作词is）

He will not come. （原句有操作词will）

He doesn't like her. （原句没有操作词）

He didn't do it. （原句没有操作词）

2 动词在句中作非谓语成分（不定式、现在分词、过去分词、动名词）

not否定非谓语动词时，直接在非谓语动词前加not。例如：

He left home early in order not to miss the first bus. （否定式不定式作目的状语）

I told him not to be late. （否定式不定式作宾补）

Not having enough money is his main problem. （否定式动名词作主语）

Not finishing his homework, he was scolded by his teacher. （否定式现在分词作状语）

I found his homework not done. （否定式过去分词作宾补）

not和isn't都可以用在否定句里，例如，He is not a teacher.他不是一个老师。isn't是is not的缩写，例如，She isn't a student.她不是一名学生。助动词do，does,are,后边都可以加not，而isn't只能是is的否定。

not和isn't用法基本一样，二者的区别如下：

两者都是否定形式，not一般用于助动词，而isn't是系动词加not形式。not一般需要搭配动词使用，而isn't可以直接使用于句中。