A boy in shorts kicks while standing in shallow water.
Boy sitting on a beach chair.
Sitting and standing are two different things.
(x)
exists e1 x1 x2 x3.(ne_nam_boy(x1) & on(e1,x2) & n_chair(x2) & of(x2,x3) & n_beach(x3) & Actor(e1,x1) & v_sit(e1))