?? ?????????????
????:1?????vx:???????vx
2??????????
3????????
4???????
5???????
?1???2??,??????????????(?)
????????:??????1???2??,??????????????(?)
????????:?????????:1?????vx:???????vx
2??????????
3????????
4???????
5???????
?1???2??,??????????????(?)
????????:?????