Complex sentence: His paternal great-grandparents, survivors of the Armenian Genocide, Hagop and Agavni Alahverdian, immigrated to the United States in 1923 after escaping to Alexandria, Egypt.
Split into simpler sentences: His paternal great-grandparents, Hagop and Agavni Alahverdian, were survivors of the Armenian Genocide. The Alahverdians immigrated to the United States in 1923 after escaping to Alexandria, Egypt.