2623. What characters can be added here so that each character contains a part of the previous character? a) 勅 -> _ -> _ -> 地 b) 案 -> _ -> _ -> 縦

a) 勅 -> 加 -> 吐 -> 地  

勅  CHOKU - imperial decree

加  KA, kuwa(eru), kuwa(waru) - add, append, join, take part

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

地  CHI, JI - earth, land

b) 案 -> 柱 -> 素 -> 縦  

案  AN - plan, proposal

柱  CHUU, hashira - pillar, column, pole

素  SO, SU - element, naked, simple

縦  JUU , tate - height, vertical