Perfluorokerosene (pfk)
[化] 全氟煤油
🗣️ 情景例句
Excuse me, but I know you from somewhere.
打扰一下，我好像在什么地方见过你。
Oh, it's a shame that you have to leave.
哦，真遗憾，你非走不可呀。
It is fairly clear that sleeping period must have some function,
很清楚，睡眠必然具有某种作用。