The dog walks across the stream on a fallen log.
The dog followed its owner across the stream.
Just because a dog walked across a stream doesn't mean it was following its owner.
exists e1 s1 x1 x2 x3.(n_stream(x2) & n_dog(x1) & on(e1,x3) & n_log(x3) & a_fallen(s1) & Theme(s1,x3) & across(e1,x2) & Actor(e1,x1) & v_walk(e1))
exists e1 x1 x2 x3.(n_stream(x3) & n_owner(x2) & of(x2,x1) & n_thing(x1) & n_dog(x1) & Theme(e1,x2) & Actor(e1,x1) & v_follow(e1) & across(x2,x3))