A small boy is riding a water slide
A small boy is standing still.
One cannot stand still while riding a water slide.
exists e1 s1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_slide(x2) & of(x2,x3) & n_water(x3) & n_boy(x1) & a_small(s1) & Theme(s1,x1))
exists e1 s1 s2 x1.(a_still(s2) & Manner(e1,s2) & Actor(e1,x1) & v_stand(e1) & n_boy(x1) & a_small(s1) & Theme(s1,x1))