is not缩写形式是isn't。
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。
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。
同近义词:
adv. 不(用于否定句)
no , non , n't。
含有not的时候,常用缩写形式。
isn't=is not;aren't=are not。
can't=can not;that's=that not。
let's=let is;my name's=my name is。