Two men t-shirts are working on a mechanical device.
the men are fixing a mechanical device
working on a mechanical device can mean fixing it.
exists e1 s1 x1 x2 x3.(on(e1,x3) & n_device(x3) & a_mechanical(s1) & Theme(s1,x3) & Actor(e1,x1) & v_work(e1) & n_t-shirt(x1) & of(x1,x2) & n_man(x2) & card_eq_2(x1))
exists e1 s1 x1 x2.(n_man(x1) & Theme(e1,x2) & Actor(e1,x1) & v_fix(e1) & n_device(x2) & a_mechanical(s1) & Theme(s1,x2))