Men wearing hard hats and safety vests are working.
Some men are building a house.
Men wearing hard hats and safety vests are working not necessarily building a house.
exists e2 e1 s1 x1 x2 x3 x4 x5.(Actor(e2,x1) & v_work(e2) & subset_of(x4,x1) & n_vest(x4) & of(x4,x5) & n_safety(x5) & subset_of(x2,x1) & n_hat(x2) & a_hard(s1) & Theme(s1,x2) & Actor(e1,x2) & v_wear(e1) & of(x2,x3) & n_man(x3))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_build(e1) & n_house(x2) & n_man(x1))