Polyfluoride
多氟化物
🗣️ 情景例句
Do you want to get together and study sometime?
你想和我一起学习吗？
Mr. Wagner, do you have a hotel reservation?
华格纳先生，你预订过旅馆吗？
The EU -- following fine continental traditions --
欧洲人遵循优良的大陆传统，