two snowboarders throw up their hands.
two snowboarders
it states there are two  snowboarders  in each sentence
exists e1 s1 x1 x2.(a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_throw(e1) & n_hand(x2) & of(x2,x1) & n_thing(x1) & n_snowboarder(x1) & card_eq_2(x1))
exists x1.(n_snowboarder(x1) & card_eq_2(x1) & a_topic(x1))