A group of kids hiking on a trail.
Kids are sitting on a trail.
One cannot be sitting while hiking simultaneously.
exists e1 x1 x2 x3 x4.(a_topic(x1) & of(x1,x2) & on(e1,x4) & n_trail(x4) & Actor(e1,x3) & v_hike(e1) & (x2 = x3) & n_kid(x2) & n_group(x1))
exists e1 x1 x2.(on(e1,x2) & n_trail(x2) & Actor(e1,x1) & v_sit(e1) & n_kid(x1))