Complex sentence: Commonly, only the chorus (which is reiterated) is played and sung at sporting events and official diplomatic ceremonies, the anthem is ended afore the first verse (the slow music) due to the chorus being the most vigorous musical part of the anthem.
Split into simpler sentences: Commonly, only the chorus (which is reiterated) is played and sung at sporting events and official diplomatic ceremonies. The anthem is ended afore the first verse (the slow music) due to the chorus being the most vigorous musical part of the anthem.