I have come across two plural spellings of international: 'internationaux' and 'internationales'. Are they both utilized?
One is for masculines, the other for feminines. Grammtacal constructions, that is.
Is there a plausible reason why Duolingo won't accept internationaux in this sentence?
I think not. The subject could be masculine or feminine. So if it's still doing that, it should be reported!