Complex sentence: Guillermo Lora (31 October 1922--17 May 2009) was a Trotskyist leader in Bolivia who was active in the Revolutionary Workers' Party (POR) from the early 1940s and was its best known leader.
Split into simpler sentences: Guillermo Lora (31 October 1922--17 May 2009) was a Trotskyist leader in Bolivia. Lora was active in the Revolutionary Workers' Party (POR) from the early 1940s and was its best known leader.