Ppb
[化] 十亿分率
🗣️ 情景例句
We have a very important meeting on at the moment.
现在我们正在开一个非常重要的会。
Yay, a hole in one!
嘿！一杆进洞！
They were not fighting men, and their harp was their passport.
他们不是作战人员，竖琴就是他们的通行证。