Children playing in a stream.
The kids are climbing trees.
One cannot be climbing a stream.
exists e1 x1 x2 x3.(a_topic(x1) & in(e1,x3) & n_stream(x3) & Actor(e1,x2) & v_play(e1) & (x1 = x2) & n_child(x1))
exists e1 x1 x2.(n_kid(x1) & Theme(e1,x2) & Actor(e1,x1) & v_climb(e1) & n_tree(x2))