Complex sentence: The Republican fighters were no match for the Bf 109, equipped mostly with Soviet built Polikarpov I-15 and Polikarpov I-16s the Republican forces suffered heavy losses to Nationalist and Condor Legion fighters.
Split into simpler sentences: The Republican fighters were no match for the Bf 109. Equipped mostly with Soviet built Polikarpov I-15 and Polikarpov I-16s the Republican forces suffered heavy losses to Nationalist and Condor Legion fighters.