天然: natural; native; living 短语和例子天然产物 be made by nature; 中国无产阶级和广大农民有天然的联系。 the chinese proletariat has natural ties with the peasant masses.; 天然宝石 [宝] natural gemstone; 天然播种 self-sowing; 天然采光
天然沥青: asphaltic bitumenbitusolcrude bitumengilsonitegrahamiteimpositeionitekeritematural asphaltnative asphaltnative bitumennativea haltnatural a haltnatural bitumennatural rock asphaltnaturala
