英訳に間違いが有れば正してください。
彼らはそのホテルに滞在中、お互いにロマンチックな気持ちを抱いていたようだった。
They appeared to have developed romantic feelings for each other during staying in the hotel.
ヒント
during
答え stayingをtheir stayにする
They appeared to have developed romantic feelings for each other during their stay in the hotel.
duringは前置詞だが動名詞は続かない
