isnot缩写形式是isn't。

1.与not相关的否定缩写：通常在原词后加n't，若原词以n结尾，直接加't。

2.系动词be、助动词、情态动词的否定形式，一般可以缩写成为一种简略的形式。如：is not—isn't、are not—aren't、was not—wasn't、were not—weren't、has not—hasn't、have not—haven't、will not—won't、do not—don't、did not—didn't、used not to—usedn't / didn't use to。



扩充.例句

1、It isn't too difficult once you get the idea

你一旦弄懂了，就不太难了。

2、Perhaps he isn't coming.

他许不来了。

3、It's past the appointed time. Maybe he isn't coming.

约定的时间都过了，别是他不来了吧？

4、He is not my brother.=He isn't my brother.