Ddm
abbr. 调制深度差（Difference of Depth of Modulation）；分布式数据管理（Distributed Data Management）
🗣️ 情景例句
He has a strong will.
他意志坚强。
For a few, scholarships were sources of support.
有少数人，奖学金是他们接受教育的学费来源。
The train was late but nobody knew the reason for the delay.
火车晚点了，但没人知道为什么。