Sffd
abbr. step-function frequency discriminator 阶跃函数鉴频器
🗣️ 情景例句
It's going to be hard, but give it your best shot.
事情会很难，你尽力而为就是了。
No. It's out of the question.
哪儿的话，根本谈不上赔。
In the afternoon, she usually sees her friends.They often drink tea together.
下午，她总是会见她的朋友。她们经常在一起喝茶。