????:1?????????:????????

2????????

3???????

4??????????

5???sn??

??????????????9???????????20??(??????????????????)9????????????????????????18?????????20??????????,??,??????????????????????“???????? ???????”???????,?????????????

??????? ?????

?????,????????????,?????,???????????????,???????,???,????,????????,????????????“???????”????????

“??????,???,??????,?,????????????????,????????????????,???,?????”???

????,????????????,??????“?”??????,????“???????????????”,???“????????????????????????????”????????????,?“????????”????????????,??,????????“??????”??,????“??”?????????

?????????????????,????????“????‘?????????????????????????????’?????”????????????????????????????????????????????????,???

????“??????????????”??????,?????????????102??????????20?????

?,????????????“???????,???”“??????,?????”“??????????,???????”????,???????????(???????)

?????:??