Sffd
abbr. step-function frequency discriminator 阶跃函数鉴频器
🗣️ 情景例句
She's a smart young lady, and very nice.
她是个聪明的年轻姑娘 而且很善良。
How deep?
多深？
Mmm, I see. It feels a bit tense. what happened exactly?
哦，我知道了。摸起来有点硬。到底发生了什么事？