Uf
abbr. 脲甲醛树脂；超声频率（Ultrasonic Frequency）
🗣️ 情景例句
Sorry, but he is out at the moment.
抱歉，他现在出去了？
He can't come and he sends his apologies.
他为他的不能前来致歉。
My watch is faster than yours.
我的表比你的表快。