????:1?51??:????

2?????????

3?????200?????

4????????

5???????????

????7???????????4??????????????

???:?????????“city?city???????”“??????????????city???????????????”?,??????????????????????

??,?,???????????????,?????????5???????????????????,?????1200????????????,??????700??????;????,?????????????????????57%??,????????????,??!

(?????????? ???)

????????:?????????