Complex sentence: They have achieved 18 Top-30 hits in Ireland, including three Number One singles, and hold the record for Ireland's biggest-selling single of all time, "I Useta Lover," which topped the Irish charts for nine consecutive weeks in 1990.
Split into simpler sentences: They have achieved 18 Top-30 hits in Ireland, including three Number One singles. They hold the record for Ireland's all-time biggest-selling single, "I Useta Lover," which topped the Irish charts for nine consecutive weeks in 1990.