natural fur天然毛皮naturaladj.自然的；天然的；私生的natural organic material天然有机质natural-gasoline plant[机] 天然汽油厂Natural frequency vector固有频率向量natural gas distribution天然气输配natural secondary forest天然次生林natural feature matching自然特征匹配natural oxidized - ore天然氧化矿natural landscape garden天型山水园natural irrigation areas自然水灌区natural avirulent strain自然弱毒株