A certain unit is preparing to hold the annual spring sports meeting  All the members of Section A participated in the 50-meter or 100-meter sprint, and some young members of the Section also participated in the 10,000-meter long-distance race
Some people infer that some of the members of the unit who participated in sprint events are long-term long-distance runners
Some of the members who took part in the 10,000-meter long-distance race are long-term  long-distance runners.