An adult sweeping stone staircase outdoors.
A child is washing a staircase.
One is an adult and the other is a child.
exists s1 x1 x2 x3 x4.(a_topic(x1) & n_outdoors(x1) & of(x1,x4) & n_staircase(x4) & of(x1,x3) & n_stone(x3) & a_sweeping(s1) & Theme(s1,x1) & of(x1,x2) & n_adult(x2))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_wash(e1) & n_staircase(x2) & n_child(x1))