People are walking through a mall.
They are in the mountains.
One cannot be in a mall and in the mountains at the same time.
exists e1 x1 x2.(through(e1,x2) & n_mall(x2) & Actor(e1,x1) & v_walk(e1) & n_people(x1))
exists p1 x1 x2.(n_mountain(x2) & n_thing(x1) & in(x1,x2))