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![](https://image.chezhanri.com/2019/0301/20190301160600795.jpg)
????:1??????????????:??????
2??????????
3?????
4???????
5?????????
???6??27?????????????????? ????????,????????????????,?????????????(ISO/TC 81)??,???
??????,????????????“???”????????????????(FAO)???,?????????????????????30%~40%????????????????????????,????,????????????????????????
ISO/TC 81??????????,?????????,??????????????
???????????????:?????????????????