732. What characters can be added here so that each character contains a part of the previous character? 架 -> _ -> _ -> 脚

Answer:

架 -> 棋 -> 期 -> 脚

架  KA, ka(keru), ka(karu) - hang, build (a bridge)

脚  KYAKU, KYA, ashi - leg

棋  KI - go, shogi, Japanese chess

期  KI, GO - time, period, term