abbr. 概率分部函数（Probability Distribution Function）
🗣️ 情景例句
and we'll go out to dinner.
然后我们到外面吃晚饭。
A good book is a best friend who never turns his back upon us.
一本好书，莫逆之交。
We walk on the garden path.
我们走在花园小径上。