Two teenagers doing tricks on skateboards.
The two boys are doing tricks on the skateboards.
The kids are not shown to be boys.
exists e1 x1 x2 x3 x4.(a_topic(x1) & on(e1,x4) & n_skateboard(x4) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & n_trick(x3) & (x1 = x2) & n_teenager(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(n_skateboard(x3) & n_boy(x1) & card_eq_2(x1) & on(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_trick(x2))