Complex sentence: He represented New Zealand at two Olympic Games in Mexico1968 and Munich1972, with his best result of 16th in the light-heavyweight grade at the 1968 Olympics.
Split into simpler sentences: He represented New Zealand at two Olympic Games, at the 1968 Mexico Olympics and at the 1972 Munich Olympics. His best result was 16th place in the light-heavyweight grade at the 1968 Olympics.