Denitrifier
[医] 脱氮菌
🗣️ 情景例句
What has kept you so busy?
什么使你这么忙？
If things were to be done twice all would be wise.
事事倘能做两次，人人都可称明智。
Still, I'm glad the bell is working again.'
不过，钟又能报时了，我还是很高兴的。”