2552. What characters can be added here so that each character contains a part of the previous character? a) 雷 -> _ -> _ -> 略 b) 劣 -> _ -> _ -> 賦

a) 雷 -> 累 -> 細 -> 略  

雷  RAI, kaminari - thunder

累  RUI - involvement, trouble, accumulation

細  SAI, hoso(i), hoso(ru), koma(kai) - thin, narrow, slender

略  RYAKU - abbreviation, omission

b) 劣 -> 加 -> 員 -> 賦  

劣  RETSU, oto(ru) - be inferior

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

員  IN - member

賦  FU - tribute, payment, installment