Complex sentence: Young entered into a polygamist marriage on January 11,1887 when he married Marion Penelope Hardy in Juarez, Mexico, by Church apostle Erastus S. Snow.
Split into simpler sentences: Young entered into a polygamist marriage on January 11,1887 when he married Marion Penelope Hardy in Juarez, Mexico. Young and Hardy were married or sealed by Church apostle Erastus S. Snow.