A dog swims in a pool.
A dog is sleeping on the bed.
It cannot be that the dog swims and is sleeping at the same time.
exists e1 x1 x2.(in(e1,x2) & n_pool(x2) & Actor(e1,x1) & v_swim(e1) & n_dog(x1))
exists e1 x1 x2.(n_bed(x2) & on(e1,x2) & Actor(e1,x1) & v_sleep(e1) & n_dog(x1))