Complex sentence: Thresher sharks are large lamniform sharks of the family Alopiidae found in all temperate and tropical oceans of the world; the family contains three species, all within the genus "Alopias".
Split into simpler sentences: Thresher sharks are large lamniform sharks of the family Alopiidae. Found in all temperate and tropical oceans of the world, the family contains three species all within the genus "Alopias".