A dog drinking from a creek.
A cat is drinking from a puddle.
dog and cat are not the same.
exists x1 x2 x3.(a_topic(x1) & from(x1,x3) & n_creek(x3) & n_drinking(x1) & of(x1,x2) & n_dog(x2))
exists e1 x1 x2.(from(e1,x2) & n_puddle(x2) & Actor(e1,x1) & v_drink(e1) & n_cat(x1))