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19?????21??,??????????????????,??????????????4~6?,??2~4?,?,???????????????6~8?,??10??????????????????4~5??,???6~8??;?6~8??????9~10??

????12??19???????????6???????:?,12???????????19????????????8????20?8?,????????????????????????????????5~6??????????????????7~8??????,????,?????????????????6~7?????8~10????;????????????????????????7~8???????????9???????????,???9??????10~11???????

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12?????19?????8?????20????8??????????,??????????????????????????????????????????????????????????????????????4~6????,?????,?????????????????7????;?????????????????????????????????7~8?????9?????

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12????????20??8????21???????8????,???????????????????????????????????????,?,?????(5~8????)??????????????????????????????????4~6????;????????????????????7~8???????

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12???21????8????????22????????????8??????????,????????????????????????????????????????????????????????????????,??,?????????(5~9????)??????????????????????????????

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