"The good-looking model speaks Swedish."
Translation:Den snygga modellen talar svenska.
Snygga works for both female and male models and snygge only for male ones. Since we don't know here, snygge should be accepted as well. Did you try it?
I tried 'snygge' (deducting from 'den snygge mannen' shortly before) and was marked wrong. I understand that the purely male form is very rarely used now, so I shall stick to 'snygga' in the future. THANKS!
Actually I use the male forms a lot. I think it depends on which part of the country you are from. But with the neutral forms you are always on the safe side of course :).
Because modell means model . Modellen means the model which is what the excercise says.