Ppm.
[医] 兆比率(百万分之几)
🗣️ 情景例句
Would you like something to drink?
你要不要喝点东西？
The more noble the more humble.
越高贵，越应谦逊。
Small boats loaded with wares sped to the great liner as she was entering the harbour.
当一艘大型班船进港的时候，许多小船载着各种杂货快速向客轮驶来。