A teenage boy does tricks on his skateboard in an area with much graffiti.
A boy sitting on the grass.
If the boy is doing tricks, then he is not sitting.
exists e1 x1 x2 x3 x4 x5 x6.(in(e1,x5) & with(x5,x6) & n_graffitus(x6) & n_amount(x6) & n_area(x5) & on(e1,x4) & n_skateboard(x4) & of(x4,x1) & n_male(x1) & Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & n_trick(x3) & n_boy(x1) & of(x1,x2) & n_teenage(x2))
exists e1 x1 x2 x3.(n_grass(x3) & a_topic(x1) & on(e1,x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_boy(x1))