These people are waiting in line on a staircase.
Dogs waiting in line on a staircase.
People waiting in line are not the same thing as dogs waiting in line.
exists e1 x1 x2 x3.(n_people(x1) & on(e1,x3) & n_staircase(x3) & in(e1,x2) & n_line(x2) & Actor(e1,x1) & v_wait(e1))
exists e1 x1 x2 x3 x4.(a_topic(x1) & on(e1,x4) & n_staircase(x4) & in(e1,x3) & n_line(x3) & Actor(e1,x2) & v_wait(e1) & (x1 = x2) & n_dog(x1))