Someone on a Nitro snowboard in midair and another person on the ground behind them.
Someone is breaking nails.
One would not snowboard and be breaking nails simultaneously.
exists s1 x1 x2 x3 x4 x5 x6.(n_ground(x6) & a_topic(s1) & subset_of(x5,s1) & on(x5,x6) & behind(x6,x1) & n_thing(x1) & n_person(x5) & -(x5 = x1) & n_person(x1) & subset_of(x1,s1) & on(x1,x2) & in(x2,x4) & n_midair(x4) & n_snowboard(x2) & (x2 = x3) & ne_org_nitro(x3) & n_person(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_break(e1) & n_nail(x2) & n_person(x1))