Ppmv
abbr. parts per million by volume 百万分体积比
🗣️ 情景例句
And miles to go before I sleep,
在我就寝前还得赶许多哩路
Therefore,we always put quality as the first consideration.
因而，我们总是把质量放在第一位来考虑。
The smoke from the fire rose and found its way outside and the light danced over the roof of the cave.
缕缕青烟从火中升起，飘出洞外，火光在洞顶上闪耀。