People are observing billboards.
There is more than one billboard.
People are observing the billboards, not billboard.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_observe(e1) & n_billboard(x2) & n_people(x1))
exists p1 x1 s1 x2 x3.((x1 = x2) & than(s1,x3) & card_eq_1(x3) & Theme(s1,x2) & a_more(s1) & n_billboard(x2))