Complex sentence: Sophie Stebnowska was married in 1781 to the Swedish opera singer Christoffer Christian Karsten, and in 1782, she was appointed premier actress and singer of the Royal Swedish Opera in Stockholm, a position she kept for 21 years.
Split into simpler sentences: Sophie Stebnowska was married in 1781 to the Swedish opera singer Christoffer Christian Karsten. In 1782, she was appointed premier actress and singer of the Royal Swedish Opera in Stockholm, a position she kept for 21 years.