Complex sentence: Marcel Dumoulin (born January 16,1905, date of death unknown) was a French weightlifter who competed in the 1928 Summer Olympics, in the 1932 Summer Olympics, and in the 1936 Summer Olympics.
Split into simpler sentences: Marcel Dumoulin (born January 16,1905, date of death unknown) was a French weightlifter. He competed in the 1928 Summer Olympics, in the 1932 Summer Olympics, and in the 1936 Summer Olympics.