天然的

• unlearned
• crude
• inartificial
• physical
• savage
• rude
• natural
• native

例句

1. 洞向地表开有出口的地下的或通向地内的中空或天然的通道
   A hollow or natural passage under or into the earth with an opening to the surface.
2. 角状物天然的或合成的，类似于角质物的物质
   A natural or synthetic substance resembling this material.
3. 钻石小的天然的或人造宝石，用作手表中的轴承
   A small natural or artificial gem used as a bearing in a watch.
4. 有些昆虫有一种天然的保护色可以防止敌人的袭击。
   Some insect have a natural camouflage which hide them from the attack of their enemy.