Complex sentence: Kaarle Leivonen (17 September 1886--1 January 1978) was a Finnish wrestler who competed in the featherweight event at the 1912 Summer Olympics.
Split into simpler sentences: Kaarle Leivonen (17 September 1886--1 January 1978) was a Finnish wrestler. He competed in the featherweight event at the 1912 Summer Olympics.