Can you say simply "Désolé, ce tissu n'est plus disponible", instead of the full phrase "Je suis désolé ce tissu n'est plus disponible." Is there some rule of usage or grammar?
The English says, ‘I’m sorry’ which is ‘Je suis desolé’. If it just said ‘sorry’, then your suggestion would be accurate.
Fair enough as a literal translation; but in conversational French, is it not the case that the "je suis" is often left off?
I put "Je suis désolée" and it was marked incorrect? I thought the ending of désolé changed according to gender and number
Same, this is clearly just Duo missing a possible gendered response...
I agree. In French conversation it's perfectly acceptable to say "désolé"
"Désolé" is used interchangeably with "je suis désolé" and means "I'm sorry". In fact I've rarely heard the latter.