Consider the following premises. forall y: U_3(y) -> S(y). forall y: S(y) -> U_3(y). forall y: U_3(y) -> ~T(y). exists y: T(y). Can we infer forall y: S(y) from them?
 From forall y: U_3(y) -> ~T(y), exists y: T(y) we can infer exists y: ~U_3(y). From forall y: S(y) -> U_3(y), forall y: U_3(y) -> S(y) we can infer forall y: S(y) <-> U_3(y). Finally, from forall y: S(y) <-> U_3(y), exists y: ~U_3(y) we can infer exists y: ~S(y), which contradicts forall y: S(y). Therefore, the answer is no.