A dog runs through the grass.
The dog is chasing a cat.
Just because the dog runs doesn't mean it is chasing a cat.
exists e1 x1 x2.(n_grass(x2) & through(e1,x2) & Actor(e1,x1) & v_run(e1) & n_dog(x1))
exists e1 x1 x2.(n_dog(x1) & Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_cat(x2))