Ppmv
abbr. parts per million by volume 百万分体积比
🗣️ 情景例句
Oh, Grandpa, I'm so happy to see you!
啊， 爷爷！ 见到您我真高兴。
After a while,we found a shady place under some poplar trees.
在一会儿以后，我们在一些白杨树下面发现了一块遮阴的地方。
He spent most of his life gathering money.
他一生大部分时间用来积聚钱财。