????:1???????vx:????????????

2???????????

3???????

4?????

5?????????

?????2?????????????????8? ??????????????????:???????????????7?????,??????????,??“???????????????????”?????????

????????????????????«??»7?????????,????,??,????????

???????,????????????????,??????????????????20%???(???50%????)???????????,?,??????????????

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

?????7???,??????,??????????????14????16????????????????????????????(????) ?????????:?????