Four men do repair work on a roof.
Four men on top of a roof.
repair work on roof shows that one is on top of the roof.
exists e1 x1 x2 x3 x4.(Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & on(x2,x4) & n_roof(x4) & n_work(x2) & of(x2,x3) & n_repair(x3) & n_man(x1) & card_eq_4(x1))
exists x1 x2 x3.(a_topic(x1) & on(x1,x2) & of(x2,x3) & n_roof(x3) & n_top(x2) & n_man(x1) & card_eq_4(x1))