Complex sentence: Bayer 04 Leverkusen Amateure first entered the highest football league in the Middle Rhine region, the Verbandsliga Mittelrhein, in 1978 and won the league in its fourth season there, in 1981.
Split into simpler sentences: Bayer 04 Leverkusen Amateure first entered the highest football league in the Middle Rhine region, the Verbandsliga Mittelrhein, in 1978. And won the league in its fourth season there, in 1981.