Complex sentence: Biimaal was the most powerful tribe in east africa from 1400-1920, built a large castles in the cost of Benadir, lower shabelle and juba to protect somali shores from the scavengers.
Split into simpler sentences: Biimaal was the most powerful tribe in east africa from 1400-1920. The Biimaal build a large castle in the cost of Benadir, lower shabelle and juba to protect somali shores from the scavengers.