Complex sentence: However, by the late 1990s Gravano had re-engaged in criminal activity and partnered with a local youth gang known as the "Devil Dogs" after his son became friends with the gang's 23-year-old leader, Michael Papa.
Split into simpler sentences: However, by the late 1990s Gravano had re-engaged in criminal activity. He partnered with a local youth gang known as the "Devil Dogs" after his son became friends with the gang's 23-year-old leader, Michael Papa.