The man is swimming in the ocean.
The man is swimming in the pool.
The man can either be swimming in the ocean or the pool, not both.
exists e1 x1 x2.(n_ocean(x2) & n_man(x1) & in(e1,x2) & Actor(e1,x1) & v_swim(e1))
exists e1 x1 x2.(n_pool(x2) & n_man(x1) & in(e1,x2) & Actor(e1,x1) & v_swim(e1))