Ufs
(uf 的第三人称 -s形式) abbr. 脲甲醛树脂；超声频率（Ultrasonic Frequency）
🗣️ 情景例句
Yes, sir.
是的 ，先生。
If you agree to carry the calf, they'll make you carry the cow.
得寸进尺。
If I get there early, I can see the doctor quickly, she thought.
“早到就能早看医生，”她想。