"Her cat is black."
Translation:Son chat est noir.
As far as I can tell, the rules change for "son" and "sa". These take on the gender of the following noun. In this case, chat is masculine, so "son" is used. So the translation is both "HER cat is black" and "HIS cat is black".
This is confusing, as "elle" and "il" do not follow this rule.
Yeah, it's confusing because in English, firstly, nouns don't have gender and, secondly, the possessive adjective depends on the gender of the possesor.. His (the boy's) apple. Her (the girl's) apple.
But in French, the possessive adjective depends on the gender of the object being possessed! So his/her apple will be 'sa pomme' only.. and never 'son pomme'.
The solution given here is correct, see: http://french.about.com/od/grammar/a/adjectives_possessive_2.htm
So I would assume that in terms of our English-brained understanding we should think of it as "its cat is black" with "its" agreeing with "cat" and having nothing to do with the gender of the cat owner? I need a mental handle to grapple with the fact that there seems to be no way to distinguish "his" from "her" cat. Is there no French equivalent to the Spanish "el gato de él" or "el gato de ella"?
One of the solutions was "sa chatte est noire". So it looks like you can use sa to distinguish that the owner is female, but you then have to add "te" to chat. Does that mean you have to make the nouns female if they are owned by a female or is this just a special case for cat. It is confusing!