Complex sentence: The Asian Development Bank (ADB) is a regional development bank established on 19 December 1966 which is headquartered in Ortigas Center located in Mandaluyong, Metro Manila, Philippines, and maintains 31 field offices around the world, to promote social and economic development in Asia.
Split into simpler sentences: The Asian Development Bank (ADB) is a regional development bank established on 19 December 1966, which is headquartered in the Ortigas Center located in Mandaluyong, Metro Manila, Philippines. The company also maintains 31 field offices around the world to promote social and economic development in Asia.