People are watching a boy on a skateboard at the top of a skate ramp.
A boy is skateboarding
A boy on a skateboard is skateboarding.
exists e1 s1 x1 x2 x3 x4 x5.(n_top(x4) & at(e1,x4) & of(x4,x5) & n_ramp(x5) & a_skate(s1) & Theme(s1,x5) & on(e1,x3) & n_skateboard(x3) & Theme(e1,x2) & Actor(e1,x1) & v_watch(e1) & n_boy(x2) & n_people(x1))
exists e1 x1.(Actor(e1,x1) & v_skateboard(e1) & n_boy(x1))