Nitrofluorene
[化] 硝基芴
??? 情景例句
A foreign diplomat grabbed his chopsticks as a historic souvenir.
一名國外的外交人員就拿起他用過的筷子，用它作為具有歷史意義的紀(jì)念品。
Last month was December,wasn't it ?
上個月是十二月，對不對？
a wave length (the horizontal distance between two wave crests),
波長（兩個浪峰間的水平距離）