[['copper age', 'chalcolithic (4500 bc - 3300 bc)', 'early chalcolithic', '4500 bc - 4000 bc', 'ubaid period in mesopotamia'], ['bronze age (3300 bc - 1200 bc)', 'early bronze age (3300 bc - 2000 bc)', 'early bronze age i', '3300 bc - 3000 bc', 'protodynastic to early dynastic period of egypt'], ['bronze age (3300 bc - 1200 bc)', 'early bronze age (3300 bc - 2000 bc)', 'early bronze age ii', '3000 bc - 2700 bc', 'early dynastic period of sumer'], ['bronze age (3300 bc - 1200 bc)', 'early bronze age (3300 bc - 2000 bc)', 'early bronze age iv', '2200bc - 2100 bc', 'first intermediate period of egypt'], ['bronze age (3300 bc - 1200 bc)', 'middle bronze age (2000 bc - 1550 bc)', 'middle bronze age i', '2100 bc - 2000 bc', 'third dynasty of ur'], ['bronze age (3300 bc - 1200 bc)', 'middle bronze age (2000 bc - 1550 bc)', 'middle bronze age ii b', '1750 bc - 1650 bc', 'second intermediate period of egypt'], ['bronze age (3300 bc - 1200 bc)', 'middle bronze age (2000 bc - 1550 bc)', 'middle bronze age ii c', '1650 bc - 1550 bc', 'hittite old kingdom , minoan eruption'], ['bronze age (3300 bc - 1200 bc)', 'late bronze age (1550 bc - 1200 bc)', 'late bronze age i', '1550 bc - 1400 bc', 'hittite middle kingdom , new kingdom of egypt'], ['bronze age (3300 bc - 1200 bc)', 'late bronze age (1550 bc - 1200 bc)', 'late bronze age ii b', '1300 bc - 1200 bc', 'middle assyrian empire'], ['iron age (1200 bc - 539 bc)', 'iron age i (1200 bc - 1000 bc)', 'iron age i b', '1150 bc - 1000 bc', 'neo - hittite states , aramean states']]
a total of 9 Period occured during the Bronze Age
a total of 9 [ENT] occured during the [ENT]