have 的否定形式应该为 don't have/haven't , has 的否定形式应该为 doesn't have/hasn't.
一、have/has做实意动词
1、解释
实意动词原形变否定形式时，在实意动词前加助动词do,do后加not, 缩写成don't。动词为三单形式时，do变为does，does后加not, 缩写成doesn't 。
所以，当have/has做动词时，have 的否定形式应该为 don't have , has 的否定形式应该为 doesn't have.
2、举例
We have some shops on the island. 改为否定形式：We don't have any shops on the island.
She has some shops on the island. 改为否定形式：She doesn't have any shops on the island.
二、have/has做助动词时
1、解释
have/has做助动词时 ,与过去分词连用构成完成时。此时，have 的否定形式应该为haven't , has 的否定形式应该为 hasn't.
2、举例
they have already gone. 改为否定形式：they haven't gone yet.
Alex has already gone. 改为否定形式：Alex hasn't gone yet.