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
A little further back, Tom.
再往后一点 Tom。
If you have any comment about these clauses, do not hesitate to make.
对这些条款有何意见，请尽管提，不必客气。
Now I could see a smaller deer next to the one my brother had pointed to.
现在我可以看见一只更小的鹿，它紧挨着我弟弟指的那一只。