Complex sentence: His father, William Arthur, was born in Dreen, Cullybackey, County Antrim in what is now Northern Ireland; he graduated from college in Belfast and emigrated to Canada in 1819 or 1820.
Split into simpler sentences: His father, William Arthur, was born in Dreen, Cullybackey, County Antrim in what is now Northern Ireland. He graduated from college in Belfast and emigrated to Canada in 1819 or 1820.