Beaverboard
n. 硬建筑纸板
🗣️ 情景例句
I'll call him right now. No point in delaying.
我现在就打给他。没有道理要拖拉。
Better deny at once than promise long.
轻诺必寡信。
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。