Complex sentence: Oleg Stefan (born Oleg Shtefanko; September 7,1959) is a Ukrainian actor who became popular in Russia after moving there to study acting and eventually became an American film actor after immigrating to the United States.
Split into simpler sentences: Oleg Stefan (born Oleg Shtefanko; September 7,1959) is a Ukrainian-born actor who became popular in Russia after moving there to study acting. He later became an American film actor after immigrating to the United States.