?? ?????????????????
????:1?????????????:????????
2??????
3??????????
4???????????
5?????vx
????????12??4????? (??????????? ????)???,???4???,????????
?????????190????,?????????????????????,190?????????????????
?????,??,????????????3???
????????3?????????,?????????,???????????????????“??”,????????????“?”?
???????,????????????????????????,????????4???,??????????,????????????????????
??????????,?,????????????????(??????) ???????:????