第(1/2)节     ???????????????·????ê?u?????????????x????÷á?????¤?????à??????xi?????????±?o????°?°???????????????????????·?·¨????????°àáá?????¤?????i???????????????u??°???????????????°x??????????·?±?±?xi?????????????????á????????????????

    ??????????????x?????????????°?°??????????±???????????????o???x?????i????????????±????à?????o????????????x???????x??????????????÷?i??????x??????????????u???è???u?¤????????????????????????x????÷?????????i???á???u?°?u?????????????????u????x?????????????????x???????????x?·????????¨???á??????°?°?????????x????o??·?????±?????????????·??u??áá???????é??

    ?????i??±??????????¤x÷xé??xé?¤???????i?????¤???????????????¤????????°?°????????°xé?????????????§?????????????o???????§?????????????????????????§?????????§????x???????????x?±??÷???????±??????°?°??????i???????÷°x???????¤????????°??????á???????????????·?i???????¤????x????x°??????????°??????????????????????xé????????°??u?????i????????????????????????·???????±??????????????x???à???i?????±??????????????°????±

    ??°?°??????§??????????????±???????????°???????x????????°?i??????????°??????????????????±

    ?·????±??????????????????é??????????????????±¨???????????????°x?????????????±??????¤x÷xé??????????????°???????°????u????????????????????????????????x?±??÷????°???±ê??????????x???????·??????????
第(1/2)节