????:1???????v:???????

2?94????

3????????

4???????????

5???app?

???????????????????1?????20??? ?????????????????????????????20??????????????????«??????????»???,?,????????????????????????,????????????????,????????

???????????????,???????,?????????,????????,???????????????????????,???????????,????????1??????21?,??????????????????????????????????????,???????,??????????????????

????,?????????,???????????;???????(?),??,???????????????????,????????????????,?????,??????????????????????60%???80%,??,?????“?”????????????“??????”?????????(?????????????????) ?????????:?????????????