Complex sentence: Longfellow retired from teaching in 1854 to focus on his writing, living the remainder of his life in Cambridge, Massachusetts, in a former headquarters of George Washington.He married his first wife Mary Potter in 1831 and she died in 1835 after a miscarriage.
Split into simpler sentences: Longfellow retired from teaching in 1854 to focus on his writing, living the remainder of his life in Cambridge, Massachusetts, in a former headquarters of George Washington. His first wife Mary Potter in 1831 and she died in 1835 after a miscarriage.