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
Since you don't have enough income,
由于你们的收入不够
Live and let live.
自己生活，也要让他人生活。
The house was completed five months ago.
是在5个月以前竣工的。