natural fur天然毛皮naturaladj.自然的；天然的；私生的natural surface coatings生物膜natural micro-fracture天然微裂缝Natural fragment warhead自然破片战斗部Natural gas in Zhengzhou郑州天然气natural concentrated gum天然浓缩胶natural racial variation天然种族变异natural attenuation unit奈培Natural immune mechanism天然免疫机制natural boundary element自然边界元natural walking velocity自然行走速度