Rr
abbr. 无线电航向信标（Radio Range-beacon）；雷达测距（Radar Ranging）；无线电接受器（Radio Receptor）；连流继电器（Reverse Relay）；阻力比（Resistance Ratio）
🗣️ 情景例句
To help scrub the building interior clean.
帮忙把建筑的内部擦洗干 。
What kind of grades did you make in college?
你在学院得到什么样的等级？
Oh, it's a short ruler. Who has a long one?
噢，这是把短尺。谁有长尺？