Complex sentence: The IIID was operated by the Royal Air Force and Fleet Air Arm as well as the air forces of Portugal (11 aircraft) and Australia which received six IIIDs, the first being delivered in August 1921.
Split into simpler sentences: The IIID was operated by the Royal Air Force and Fleet Air Arm as well as the air forces of Portugal (11 aircraft) and Australia. Australia received six IIIDs, the first being delivered in August 1921.