2479. What characters can be added here so that each character contains a part of the previous character? a) 章 -> _ -> _ -> 堤 b) 翌 -> _ -> _ -> 肥

a) 章 -> 古 -> 吐 -> 堤  

章  SHOU - chapter, badge, mark

古  KO, furu(i) - old

吐  TOU, ha(ku) - spew, vomit, give vent to

堤  TEI, tsutsumi - bank, embankment, dike

b) 翌 -> 音 -> 明 -> 肥  

翌  YOKU - next, following

音  ON, IN, oto, ne - sound

明  MEI, MYOU, aka(rui), a(keru) - bright

肥  HI, koe, ko(yashi), ko(yasu) - manure, fertilizer, grow fat