1940. What characters can be added here so that each character contains a part of the previous character? a) 翌 -> _ -> _ -> 鳴 b) 弦 -> _ -> _ -> 判

a) 翌 -> 辛 -> 古 -> 鳴  

翌  YOKU - next, following

辛  SHIN, kara(i) - hot, spicy, trying

古  KO, furu(i) - old

鳴  MEI, na(ku), na(ru)(rasu) - cry, sing, howl, ring

b) 弦 -> 畜 -> 畔 -> 判  

弦  GEN, tsuru - string, bowstring

畜  CHIKU - animal raising, domestic animal

畔  HAN - rice paddy ridge, levee

判  HAN, BAN - stamp, seal, paper size