53．A．tough                  B．helpless               C．various                D．valuable

52．A．strengthen           B．change                C．repeat                 D．realize

51．A．interesting           B．colorful               C．easy                    D．hopeful

50．A．cure                    B．danger                C．comfort               D．difficulty

49．A．benefit                B．harm                   C．affect                  D．change

48．A．thin                    B．dying                  C．ripe                    D．strong

47．A．More or less        B．Now and then      C．Sooner or later     D．Here and there

46．A．thank                  B．defence               C．shade                  D．death

45．A．protected             B．tied                     C．beat                    D．wrapped

44．A．rough                 B．free                    C．available             D．poisonous