Complex sentence: In May 1960, Chang was a candidate in the election for fifth congressman of the South Korean National assembly leading the New Group in the Democratic Party (민주당 신파, 民主黨 新派).
Split into simpler sentences: In May 1960, Chang was a candidate in the election for a National Assembly seat. At the time, he was the leader of the New Group in the Democratic Party (민주당 신파, 民主黨 新派).