What I'd like to understand better is why use 'has' in a postive sentence and 'have' in a negative sentence. For example:
She has red hair, she does not haveblack hair. The woman has black hair, she does not have red hair. The man has a brown moustache, he does not have a beard. The girl has curly hair, she does not have straight hair. The boy does not have long hair, he hasshort hair.