Answer:
堅 KEN, kata(i) - firm, hard, solid
東 TOU, higashi - east
肖 SHOU - resemble
囚 SHUU - arrest, imprison, prisoner
竹+咸 CHIKU, take - bamboo / KAN, GEN, mina - together, united
They all take the "fish" radical (魚 GYO, sakana, uo - fish) to become other characters.
鰹 katsuo - bonito
鰊 nishin - herring
鮹 tako - octopus
鰮 iwashi - pilchard
鱵 sayori - sajori, halfbeak