La estructura básica del negativo del presente perfecto:



Suj 
Aux Not
Verbo
   
I have not eaten
something.
No he comido algo.
You have not talked
to somebody.
no has hablado con alguien.
He has not listened
to something.
No ha escuchado algo. (él)
She has not read
something.
No ha leído algo. (ella)
It has not gone
somewhere.
No ha ido a algún sitio.
We have not looked
at something.
No hemos mirado algo.
You have not worn
something.
No habéis llevado algo puesto.
They have not sat
somewhere.
No se han sentado en algún sitio.

Nota: Contracciones: Se suele contraer "It has" con "it's", "it has not" con "it hasn't", "you have" con "you've", "we have not" con "we haven't", etc.