Answer:
老+日 ROU, o(iru), fu(keru) - grow old / NICHI, JITSU, hi, ka - sun, day
豊 HOU, yuta(ka) - abundant, rich
非 HI - mistake, non-
祭 SAI, matsu(ru), matsu(ri) - deify, worship, festival
平 HEI, BYOU, taira, hira - flat, level
They all take the "fish" radical (魚 GYO, sakana, uo - fish) to become other characters.
鰭 hire - fin
鱧 hamo - a type of eel
鯡 nishin - herring
鰶 konoshiro - herring, shad
鮃 hirame - flounder, halibut