Rrt
abbr. 快速軌道交通（Rail Rapid Transit）；會合雷達應答器（Rendezvous Radar Transponder）
??? 情景例句
but when I received the letter
但是當我收到那封信
It's nothing.
小事情；不足掛齒。
He had been obliged to join the army during the Second World War.
年齡比他兩個弟弟大很多，第二次世界大戰期間被迫參軍。