4 · Society, Civilization, Culture
43 · recreation, amusement
43C · sports, games and physical performances
43C7 · children's games and plays
43C72 · games using special objects (marbles, top, hoop, etc.)
43C727 · roller-skating, roller-skates
43C727(+4) ·
roller-skating, roller-skates (+ requirements, necessaries ~ sports and games)