"Does he sing better than Peter?"

Translation: क्या वह पीटर से अच्छा गाता है?

[VIJAYRAMPE1]

Here in the adverbial sense is अच्छा used instead of बेहतर to mean "better"?

[zeebo7]

"वह noun से adj. verb है" is the way of saying "He/she verbs more adj. than noun". The adverb construction is (usually) 'adj. से verb', so it's a bit of a different situation then the sentence here. Anyway, both अचछा and बेहतर should be fine here I believe.

[BrennaDP]

I originally had "क्या वह पीटर से गाता अच्छा है?" and it was counted as wrong.

I'm guessing the issue is that I had the adverb after the verb?