穴埋め問題でよく出るから注意しろ！【 arm, arms, air, airs, ash, ashes, custom, customs, force, forces, advice, advices, good, goods, manner, manners, sand, sands, ruin, ruins, spectacle, spectacles, work, works, color, colors, day, days, pain, pains, quarter, quarters, spirit, spirits 】単数形と複数形では意味が全然違う！代表的な単語はコレだ！