A man drives a yellow vehicle.
The man is riding on top of an elephant.
The subject cannot drive an elephant and a vehicle.
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_drive(e1) & n_vehicle(x2) & a_yellow(s1) & Theme(s1,x2) & n_man(x1))
exists e1 x1 x2 x3.(n_man(x1) & on(e1,x2) & of(x2,x3) & n_elephant(x3) & n_top(x2) & Actor(e1,x1) & v_ride(e1))