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
One apple. Two apples. Three apples. Four apples.
一个苹果。两个苹果。三个苹果。四个苹果。
In the world, who knows not to swim goes to the bottom.
处世似游泳，不会即下沉。
no crowd or movement in which he may take comfort,
找不到伙伴和活动使自己得到安逸。