The dressed up young people are sitting in chairs while they wait.
There are no people waiting.
There are young people waiting, so there can't be no people.
exists e1 e2 p1 s1 x1 x2.(n_thing(x1) & n_people(x1) & a_young(s1) & Theme(s1,x1) & r_up(x1) & Theme(e1,x1) & v_dress(e1) & exists e3.(Actor(e3,x1) & v_wait(e3)) & while(e2,p1) & in(e2,x2) & n_chair(x2) & Actor(e2,x1) & v_sit(e2))
exists p1 x1.-exists e1 x2 x3.((x1 = x2) & Actor(e1,x3) & v_wait(e1) & (x2 = x3) & n_people(x2))