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
Always remember to wash your hands before eating.
用餐前谨记要洗手。
Put the receiver closer to your mouth.I can't hear you.
把听筒放近你的嘴，我不能听见你的话。
See you next Friday.
下星期五见。