abbr. 概率分部函数（Probability Distribution Function）
🗣️ 情景例句
We haven't heard from him for weeks but we're still hoping for a letter.
我们已经有几个星期没有他的消息，但仍然盼望着他的来信。
Excuse me for that.
对不起我为那件事。
It's just the matter of the schedule,that is,if it is convenient of you right now.
如果你们感到方便的话，我想现在讨论一下日程安排的问题。