???????????????????2??????21????????????????????? (??????? ?????????)???,???????????,????????????????????????21???????????????????,????,??,???,?????????????????“???????”????????,???

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

???2????????????????????H?????????????????,?????“????????”??“??”????????,???????????????????????????????????????,??????????,?“??????????”???????????????????,??????????????????????????????????

????????????,????,???????????“????”?,???????????????????????????????????????,??1?????????,??????????360°???????????????,?????????????,?,????????????????????

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

????????????:??????? “????????????”????

?? ????????“????”??????

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

2????????

3?????????????

4????????v

5????????????

???????????????????2??????21????????????????????? (??????? ?????????)???,???????????,????????????????????????21???????????????????,????,??,???,?????????????????“???????”????????,???

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

???2????????????????????H?????????????????,?????“????????”??“??”????????,???????????????????????????????????????,??????????,?“??????????”???????????????????,??????????????????????????????????

????????????,????,???????????“????”?,???????????????????????????????????????,??1?????????,??????????360°???????????????,?????????????,?,????????????????????

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

????????????:???????