Group of people on the rooftop of a building looking down.
the people are on top of a building.
not all the people are reunited in groups
exists e1 s1 s2 x1 x2 x3 x4.(n_rooftop(x2) & ne_org_group(s1) & a_topic(s1) & of(s1,x1) & a_down(s2) & Manner(e1,s2) & Actor(e1,x4) & v_look(e1) & (x1 = x4) & on(x1,x2) & of(x2,x3) & n_building(x3) & n_people(x1))
exists p1 x1.(n_people(x1) & exists x2 x3.(on(x1,x2) & of(x2,x3) & n_building(x3) & n_top(x2)))