Complex sentence: The Spitfire V, which was flown by the RAF had been a match for the Bf 109F, however, the Germans had introduced an new fighter: the Focke-Wulf Fw 190.
Split into simpler sentences: The Spitfire V., which was flown by the RAF had been a match for the Bf 109F. However, the Germans had introduced an new fighter: the Focke-Wulf Fw 190.