????:1?????:?????

2???????

3?????600??

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

5???9598??

?????????11?????????????28??????????????? (??????? ??????????????)?????????????????L2??????????????L4????,28?,?(????)???????????????

??????????????????,???10????????,?????????????????????????????????,??????????

???(????????)???????????????????,???????“????”???,??????????????????,???????????????

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

????“???”?????????????????????????,???????????????????(??) ?????:???????