Complex sentence: He won 8 of 9 during the 1975 season and also won 19 of 23,20 of 26 and 21 of 29 downhills.
Split into simpler sentences: He won 8 of 9 during the 1975 season. He also won 19 of 23,20 of 26 and 21 of 29 downhills.