During a Portuguese lesson, a teacher asked us to choose an adverb for the sentence “O menino correu _______ (rapidamente / depressa).”
To me it’s like both words could be used. However, the teacher said it’s better to use depressa because rapidamente is not a proper adverb for this sentence. The teacher also mentioned the adverb of ending in “-mente” should be used in a way different from those adverb like depressa, devagar, etc. I was very confused and really cannot figure out the difference.
From my perspective, either one is valid in this sentence, although depressa would be the preferred everyday choice. Have you asked your teacher for further clarification on their position?