A group of people on a mountain trail.
People are camping
people on mountain cannot be people are camping at the same time
exists x1 x2 x3 x4.(a_topic(x1) & of(x1,x2) & on(x2,x3) & n_trail(x3) & of(x3,x4) & n_mountain(x4) & n_people(x2) & n_group(x1))
exists e1 x1.(Actor(e1,x1) & v_camp(e1) & n_people(x1))