One person is diving into the water.
Someone is diving.
One person is diving simply means someone is diving
exists e1 x1 x2.(n_water(x2) & into(e1,x2) & Actor(e1,x1) & v_dive(e1) & n_person(x1) & card_eq_1(x1))
exists e1 x1.(Actor(e1,x1) & v_dive(e1) & n_person(x1))