Ppa
abbr. 苯丙醇胺（phenyl-propanolamine）；并行处理自动机（Parallel Processing Automata）；实验性反应堆（Preliminary Pile Assembly）
🗣️ 情景例句
An apple a day keeps the doctor away.
每天一个苹果不用看医生。
My brother wants to learn how to speak Chinese.
我的兄弟要去学中国话。
and realized that it was a sign that the child was growing up and developing valuable powers of observation and independent judgment,
并且意识到这象征着孩子们正在成熟和发展宝贵的观察力、独立判断力，