Someone skateboarding down a wheelchair ramp in front of a tall yellow building.
The wheelchair ramp is empty.
it is not possible to have an empty wheelchair and a someone skateboarding at the same time
exists e1 s1 s2 s3 x1 x2 x3 x4 x5 x6.(a_topic(x1) & a_down(s3) & Manner(e1,s3) & Theme(e1,x3) & Actor(e1,x2) & v_skateboard(e1) & in(x3,x5) & of(x5,x6) & n_building(x6) & a_yellow(s2) & Theme(s2,x6) & a_tall(s1) & Theme(s1,x6) & n_front(x5) & n_ramp(x3) & of(x3,x4) & n_wheelchair(x4) & (x1 = x2) & n_person(x1))
exists s1 x1 x2.(n_ramp(x1) & of(x1,x2) & n_wheelchair(x2) & Theme(s1,x1) & a_empty(s1))