Ppb
[化] 十亿分率
🗣️ 情景例句
I want to. I haven't paid for your dinner for a long time.
我要做。我好久没帮你付吃饭的钱了。
I go downstairs and have my breakfast.
我下楼吃早饭。
you will realize that a modern navy is a good place to study noise.
你就会认识到现代海军是研究噪音的好地方。