Complex sentence: The Friedrichshafen G.I through G.IV were a series of medium bombers that were designed and manufactured by Flugzeugbau Friedrichshafen GmbH and were used by the German Imperial Air Service (the "Luftstreitkräfte") during the First World War for tactical and limited strategic bombing operations.
Split into simpler sentences: The Friedrichshafen G.I through G.IV were a series of medium bombers that were designed and manufactured by Flugzeugbau Friedrichshafen. They were used by the German Imperial Air Service (the "Luftstreitkräfte") during the First World War for tactical and limited strategic bombing operations.