II. 完形填空(共20小题,每小题1分.满分20分)阅读下面短文.掌握其大意.然后从 21-40题各题所给的四个选项中.选出可以填入空白处的最佳选项. Thr

II. 完形填空（共20小题；每小题1分，满分20分）阅读下面短文，掌握其大意，然后从   21—40题各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。

Throughout history man has had to accept the fact that all living things must die. But people now live longer than they   21  . Yet, all living things still show the   22   of aging, which will eventually   23   death.

Aging is not a disease, but as a person passes maturity (成熟期), the cells of the body and the  24   they form do not function as well as they   25   in childhood and teenage years. The body provides less   26  against disease and is more   27   to have accident.

A number of related causes may   28  aging. Some cells of the body have a fairly long life, but they are not   29   when they die. As a person ages,   30   of brain cells and muscle cells decreases.   31   body cells die and are replaced by new cells. In an aging person the   32  cells may not be as workable or as capable   33   growth as those of a young person.

Another   34   in aging may be changes within the cells   35   . Some of the protein chemicals in cells are known   36  with age and become less elastic (有弹性的). This is why the skin of old people wrinkles (皱纹) and   37 . This is also the reason why old people   38   in height. There may be other more important chemical changes in the cells. Some complex cell chemicals, such as DNA and RNA, store and   39   information that the cells need． Aging may affect this   40   and change the information-carrying molecules so that they do not transmit the information as well.

21. A．would             B．be used to               C．used to            D． used

22. A．function       B．effect              C．affect          D． appearance

23. A．lead in         B．give in                    C．run into          D． result in

24. A．hands          B．feet                       C．heart              D． organs

25. A．do            B．has done                C．did                D． had done

26. A．energy        B．protection             C．vigor          D． power

27. A．likely          B．probable               C．possible          D． alike

28. A．attend to        B．contribute to          C．add to           D． devote to

29. A．replaced       B．reborn                  C．recovered      D． surrendered

30. A．a number       B．the amount           C．the number   D． a great deal

31. A．The others           B．The other           C．Another        D． Other

32. A．old            B．left                           C．new           D． other

33. A．to             B．for                     C．of             D． in

34. A．factor          B．effect                         C．reason           D． element

35. A．for themselves B．of themselves        C．themselves     D． on their own

36.   A．change          B．to have changed     C．to change      D． to be changed

37. A．hangs loose                                       B．hangs loosely  

    C．is hanging loosely                                D．is hanging loose

38. A．increase         B．shrink                  C．lengthen        D． decrease

39. A．pass away      B．pass by                 C．pass off         D． pass on

40. A．improvement  B．procession            C．approach       D． process

试题答案

CBDDC   BABAC   DCCAC   CABDD