Present simple negative

[Myc]

is it
she doesn't have a cat

or is it
she dosen't has a cat?

have sounds right according to my ear, but don't you use "has" with third person singular pronouns? as in " she has a dog", you don't say "she have a dog".

Thanks

[Conchita]

The correct sentence is: She doesn't have a cat.

Auxiliaries agree with the subject and are followed by the infinitive of the main verb.

[Jamie (K)]

To add to what Conchita said, think of it this way:

The auxiliary "does" already has the final S for person and number, so the main verb doesn't need it. You shouldn't have it twice.