Consider the following premises. forall x_4: S(x_4) or ~U_3(x_4). S(a) -> w_3. Can we infer U_3(a) -> w_3 from them?
 From forall x_4: S(x_4) or ~U_3(x_4) we can infer forall x_4: U_3(x_4) -> S(x_4). From forall x_4: U_3(x_4) -> S(x_4) we can infer U_3(a) -> S(a). Finally, from U_3(a) -> S(a), S(a) -> w_3 we can infer U_3(a) -> w_3. Therefore, the answer is yes.