Because he's an open mouth sleeper, he says he has to floss more to help prevent gum disease, and so I asked him how often he flosses, and he said, "Every other day."
因为他是那种张嘴睡觉的人， 他说他需要更频繁地使用牙线， 以预防牙周病。 所以我问他用牙线有多频繁， 然后他回答说，“两天一次。”