Three people standing in the snow behind a No Skiing sign.
Skiers are pulled by the boat.
Three people cannot be in two different places at the same time as well as it is hardly imaginable how skiers are pulled by the boat.
exists e1 x1 x2 x3 x4 x5 x6.(n_snow(x3) & a_topic(x1) & behind(e1,x4) & n_sign(x4) & of(x4,x6) & n_skiing(x6) & (x4 = x5) & ne_nam_no(x5) & in(e1,x3) & Actor(e1,x2) & v_stand(e1) & (x1 = x2) & n_people(x1) & card_eq_3(x1))
exists e1 x1 x2.(n_boat(x2) & Actor(e1,x2) & Theme(e1,x1) & v_pull(e1) & n_skier(x1))