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
Yes.
是的。
What is the longest river in this country?
这个国家最长的河是什么？
They support the cables from which the bridge has been suspended.
高塔支撑着钢缆，而钢缆又悬吊着大桥，