the dog barks at the toy.
The dogs are fighting over the toy.
The dogs are not necessarily fighting over the toy.
exists x1 x2 x3.(n_toy(x3) & n_bark(x1) & of(x1,x2) & n_dog(x2) & a_topic(x1) & at(x1,x3))
exists e1 x1 x2.(n_toy(x2) & n_dog(x1) & over(e1,x2) & Actor(e1,x1) & v_fight(e1))