Efc
abbr. earth fixed coordinate 固定坐标系; electronic feedback carburetor 电子反馈汽化器; engineered for color 彩色（电视机）工程; Evergreen Fir Corporation (initials) 常青枞树公司（组织名称的第一个字母）
🗣️ 情景例句
He's the Dean of Admissions for the University of Michigan.
他是Michigan大学的新生注册主任。
To have a baby
有了孩子
Hi! You guys keep talking so loudly that I have to speak at the top my voice!
哎！你们一直这样大声讲话，我都不得不扯着嗓子说话了。