Downhill skier kicks and a plume of snow.
A man water skis behind the boat
One person using water skis while the other is using snow skis
exists s1 x1 x2 x3 x4 x5.(a_topic(s1) & subset_of(x4,s1) & of(x4,x5) & n_snow(x5) & n_plume(x4) & subset_of(x1,s1) & n_kick(x1) & of(x1,x3) & n_skier(x3) & (x1 = x2) & ne_nam_downhill(x2))
exists x1 x2 x3 x4.(n_boat(x4) & a_topic(x1) & behind(x1,x4) & n_ski(x1) & of(x1,x3) & n_water(x3) & of(x1,x2) & n_man(x2))