A boy on a skateboard is at the top of a ramp.
The boy is smiling
The boy on the skateboard may not be smiling at all.
exists p1 x1 x2 x3.(n_top(x3) & exists x4.(at(x1,x3) & of(x3,x4) & n_ramp(x4)) & on(x1,x2) & n_skateboard(x2) & n_boy(x1))
exists e1 x1.(n_boy(x1) & Actor(e1,x1) & v_smile(e1))