Complex sentence: Since April 1944, the "Triangular Sword Competition"--a format between Newbridge College, Clongowes Wood College and the Irish Army Cadet School--has taken place without fail, involving golf, gaelic football, soccer, swimming, athletics and basketball.
Split into simpler sentences: Since April 1944, the "Triangular Sword Competition"--a format between Newbridge College, Clongowes Wood College and the Irish Army Cadet School--has taken place without fail. It involves six sports; golf, gaelic football, soccer, swimming, athletics and basketball.