Complex sentence: A few days later, on 4 June 1948, they founded Omonia Nicosia Football Club, which (until today) is the arch rival of APOEL and there has been a traditional animosity between the fans of the two teams.
Split into simpler sentences: A few days later, on 4 June 1948, they founded Omonia Nicosia Football Club. Omonia is to this date the arch rival of APOEL and there has been a traditional animosity between the fans of the two teams.