短语词组短語zero lift line 無陞力線;零陞力線zero grade line 施工基準線;路基施工準則線zero reactance line 零電抗線zero mean line 零均線zero stress line 零應力線zero accumulative line 零點收歛指數zero base line 零基線zero layer line 零層線;中層線Zero wind line 零風線 返回 zero line