Original: The baleen whales, also called whalebone whales or great whales, form the Mysticeti, one of two suborders of the Cetacea (whales, dolphins, and porpoises).
Simplified: The baleen whales, also called whalebone whales or great whales, make up the Mysticeti, one of the two groups of the Cetacea (whales, dolphins, and porpoises).