Several children are seated in the sand, one of whom is looking at a soccer ball.
A couple of children are alone at the park
Just because several children are seated in the sand, one of whom is looking at a soccer ball does not mean they are alone at the park.
exists e2 e1 s1 x1 x2 x3 x4 x5 x6.(n_sand(x2) & at(e2,x5) & n_ball(x5) & of(x5,x6) & n_soccer(x6) & Actor(e2,x4) & v_look(e2) & of(x4,x3) & n_one(x4) & in(e1,x2) & (x2 = x3) & Theme(e1,x1) & v_seat(e1) & n_child(x1) & a_several(s1) & Theme(s1,x1))
exists s1 x1 x2 x3.(n_park(x3) & at(s1,x3) & Theme(s1,x1) & a_alone(s1) & of(x1,x2) & n_child(x2) & n_couple(x1))