freeairadj.大气的(自由空间)freeadj.自由的；免费的；畅通的；没有…的；未使用的；空闲的；随意的v.释放；使自由；使摆脱；解除；使可用于(某目的)adv.免费地；自由地free-falling classifier自由沉降分级机free and forced vibration自由振动和受迫振动free energy of activation激活的自由能,自由活化能,活化自由能freezing and thawing soil冻融土壤free hydrocarbon in pores孔隙游离烃Freezing-thawing period季节性冻融期free trade zone in Ningbo宁波自由贸易区free convertible currency可自由兑换通货free-machining addition改善切削性添加剂freezing-thawing damage冻融破坏