Eiderdowns
n. 鸭的绒毛, 鸭绒被( eiderdown的复数形式 )
🗣️ 情景例句
May I ask who's calling?
请问你是谁？
He who has not tasted bitter knows not what sweet is.
不吃苦中苦，哪知甜中甜。
This depends on the precise radio frequency of the 21-cm wavelength, or 1420 megacycles per second.
这种通讯联系要靠21厘米波段，即每秒1420兆周的精确无线电频率。