Complex sentence: The Buddhist crisis was a period of political and religious tension in South Vietnam from May 1963 to November 1963 characterized by a series of repressive acts by the South Vietnamese government and a campaign of civil resistance, led mainly by Buddhist monks.
Split into simpler sentences: The Buddhist crisis was a period of political and religious tension in South Vietnam from May 1963 to November 1963. It was characterized by a series of repressive acts by the South Vietnamese government, and a campaign of civil resistance which was mainly led by Buddhist monks.