People with numbers on their chests are running in a pack.
People in a race are grouped together.
People with numbers are called to be group, and race in the sense is  called running.
exists e1 x1 x2 x3 x4.(in(e1,x4) & n_pack(x4) & Actor(e1,x1) & v_run(e1) & on(x1,x3) & n_chest(x3) & of(x3,x1) & n_thing(x1) & with(x1,x2) & n_number(x2) & n_people(x1))
exists e1 p1 x1 x2.(exists s1.(Theme(s1,x1) & a_together(s1)) & Recipient(e1,p1) & Topic(e1,x1) & v_group(e1) & in(x1,x2) & n_race(x2) & n_people(x1))