Why it doesn't accept the answer with "more strong" and not "powerful"?

Thanks for the response.

Yes, I think it will work such answer, but still, I think that "more strong" should be added to correct answers as well. Bcs they give here the translation for "mai puternici" as "more powerful", but do not accept "more strong".

I am not complaining, the team have done a great job of adding Romanian to Duolingo, just think that it should be fixed :)