The best method for preventing melasma from forming, worsening, or recurring is strict sun avoidance. 最好的预防黄褐斑的形成,恶化,或反复出现的方法的是防晒。
An implement with cutting edges or a pointed end for boring holes in hard materials,usually by a rotating abrasion or repeated blows. 钻带切割刃或尖端的工具,用于在坚硬材料上钻孔,一般靠旋转磨损或反复击打实现钻孔。