A man is waterskiing on one ski.
He is driving the boat very fast.
A SKI IS NOT A BOAT
exists e1 x1 x2.(on(e1,x2) & n_ski(x2) & card_eq_1(x2) & Actor(e1,x1) & v_waterskie(e1) & n_man(x1))
exists e1 s1 x1 x2.(n_boat(x2) & n_male(x1) & r_very(e1) & a_fast(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_drive(e1))