Qac
abbr. quaternary ammonium compound 季铵化合物（杀菌剂）
🗣️ 情景例句
But I have a doctor's appointment in the afternoon.
但我后天下午跟医生约好了。
How! A fight!
哗，打架啦！
People are not so honest as they once were.
人们不再像以前那样诚实了。