Polyacetaldehyde
聚乙醛
🗣️ 情景例句
What are your greatest achievement?
你最大的成就是什么？
Put the receiver closer to your mouth.I can't hear you.
把听筒放近你的嘴，我不能听见你的话。
He simply had no sense of danger at all.
而是他压根儿没有一点儿危险感。