Answer:
a) 婆 -> 如 -> 吟 -> 含
婆 BA - old woman
如 JO, NYO - equal, like, as, as if
吟 GIN - sing, chant, recite
含 GAN, fuku(mu), fuku(meru) - hold, include, contain
b) 誓 -> 計 -> 古 -> 味
誓 SEI, chika(u) - swear, pledge, vow
計 KEI, haka(ru), haka(rau) - plan, total, measure
古 KO, furu(i) - old
味 MI, aji , aji(wau) - taste