A group of people in army pants running.
The group of runners are practicing for a race.
You  can not infer they are runners.
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & Actor(e1,x5) & v_run(e1) & (x1 = x5) & of(x1,x2) & in(x2,x3) & n_pants(x3) & of(x3,x4) & n_army(x4) & n_people(x2) & n_group(x1))
exists e1 x1 x2 x3.(n_group(x1) & for(e1,x3) & n_race(x3) & Actor(e1,x1) & v_practice(e1) & of(x1,x2) & n_runner(x2))