Fra
abbr. 联邦铁路局（Federal Railroad Administration）；联邦储备法（Federal Reserve Act）；流量警报记录器（Flow Alarm Recorder）；自由基型（Free Radical Type）
🗣️ 情景例句
I'm so busy that I don't get around to it.
我忙得找不出时间去做它。
An old poacher makes the best keeper.
老偷猎者是最好的看守人。
It has been found that certain bats emit squeaks and by receiving the echoes,
人们发现，某些蝙蝠能发出尖叫声，