?? ???????????8????????????

????:1????????:????????????
2?????
3??????????
4???????
5?????wx
???2??????21??????????????? (?? ???????????????)21???????????,???????8???????
??????,??????????,????????????????????,????????4?????4?????????,????????????????????????????????????????????,???????“????????????”??????????????????????????????,?????????????,???????????????
???????????????????,??,???????????,?????“?”?“1+N”?????????????????,????????????????????,???????,???,??,???????????????,?????????????????????????????,??,????(????)
??:??????