Complex sentence: Former Representative from Cebu Bartolome Cabangbang was one of the candidates in the 1981 presidential election overwhelmingly won incumbent president Ferdinand Marcos that was boycotted by most opposition parties when their candidate, Benigno Aquino, Jr., was barred from running.
Split into simpler sentences: Former Representative from Cebu Bartolome Cabangbang was one of the candidates in the 1981 presidential election overwhelmingly won by the incumbent president Ferdinand Marcos. This election was boycotted by most opposition parties when their preferred candidate, Benigno Aquino, Jr., was barred from running.