A waterskier flies into the air.
A waterskier has crashed into the water.
A waterskier cannot be fly into the air while crashed into the water.
exists e1 x1 x2.(n_air(x2) & into(e1,x2) & Actor(e1,x1) & v_fly(e1) & n_waterskier(x1))
exists e1 x1 x2.(n_water(x2) & into(e1,x2) & Actor(e1,x1) & v_crash(e1) & n_waterskier(x1))