a boy jumps into the pool.
The boy was playing at the pool.
If the boy jumps into the pool then he had to playing at the pool to be able to jump into it.
exists e1 x1 x2.(n_pool(x2) & into(e1,x2) & Actor(e1,x1) & v_jump(e1) & n_boy(x1))
exists e1 x1 x2.(n_pool(x2) & n_boy(x1) & at(e1,x2) & Actor(e1,x1) & v_play(e1))