Complex sentence: He also spent some time working in Dublin, Ireland in 1774 and 1775; his opera "The Maid of the Vale" premiered at the Smock Alley Theatre in Dublin on 12 February 1775.
Split into simpler sentences: He also spent some time working in Dublin, Ireland in 1774 and 1775. His opera "The Maid of the Vale" premiered at the Smock Alley Theatre in Dublin on 12 February 1775.