Is there a difference between using
etre a + moi/toi/lui/...
and
possessive pronous?
Or could they be used interchangeably? Are there certain situations in which one would be better than the other?
For example:
Ces lunettes de soleil ne sont pas les siennes.
Those sunglasses are not his.Would it also be appropriate to say: Ces lunettes de soleil ne sont pas à eux.