699. What characters can be added here so that each character contains a part of the previous character? 暗 -> _ -> _ -> 吹

Answer:

暗  AN, kura(i) - dark

吹  SUI, fu(ku) - blow

暗 -> 章 -> 古 -> 吹

章  SHOU - chapter, badge, mark

古  KO, furu(i) - old