Khn
[医][=Knoop hardness number]努普（氏）硬度值
🗣️ 情景例句
Safety first.
安全第一。
He didn't visit this country on the tour.
他在旅行中不拟访问这个国家。
First it made a circle to the right, then to the left.
令他吃惊的是，蜜蜂开始在蜂窝的表面表演一种舞蹈。