The snowboarder is sitting down.
The snowboarder is sitting donw.
The sentence can be inferred from the previous sentence.
exists e1 s1 x1.(n_snowboarder(x1) & a_down(s1) & Manner(e1,s1) & Actor(e1,x1) & v_sit(e1))
exists p1 x1.(n_snowboarder(x1) & exists e1 x2.((x1 = x2) & n_donw(x2) & Actor(e1,x2) & v_sit(e1)))