 Complete the following phrase:  The UEFA European Football Championship, less formally the European Championship and informally the Euros, is the primary association football tournament organized by the Union of European Football Associations UEFA. The competition is contested by UEFA members senior mens national teams, determining the continental champion of Europe. The competition has been held every four years since 1960, except for 2020, when it was postponed until 2021 due to the COVID-19 pandemic in Europe, but kept the name Euro 2020. Scheduled to be in the even-numbered year between FIFA World Cup tournaments, it was originally called the European Nations Cup, changing to the current name in 