A skier catches air over the snow.
A person is skiing.
A skier is a person that skies
exists e1 x1 x2 x3.(n_snow(x3) & over(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_catch(e1) & n_air(x2) & n_skier(x1))
exists p1 x1.(exists x2.((x1 = x2) & n_skiing(x2)) & n_person(x1))