12. His attitude toward study impedes his progress. (A) affects (B) effects (C) hinders (D) enhances (E) stimulates

17. Recently many major politicians were hospitalized for serious cases of illness. Doctors said that it was because irregular living habits, heavy smoking and drinking, as well as long periods of work under stress had taken the toll. (A) cost the money (B) paved the road (C) enjoyed the game (D) done the damage (E) killed the life .