A young skateboarder rolls down a graffiti-covered ramp.
A teenage boy is skateboarding at the park.
The young skateboarder does not have to be a teenage boy.  The graffiti-covered ramp does not have to be at a park.
exists e1 s1 s2 s3 x1 x2.(a_down(s3) & Manner(e1,s3) & Theme(e1,x2) & Actor(e1,x1) & v_roll(e1) & n_ramp(x2) & a_graffiti-covered(s2) & Theme(s2,x2) & n_skateboarder(x1) & a_young(s1) & Theme(s1,x1))
exists e1 x1 x2 x3.(n_park(x3) & at(e1,x3) & Actor(e1,x1) & v_skateboard(e1) & n_boy(x1) & of(x1,x2) & n_teenage(x2))