Subfluoride
低氟化物, 氟化低价物
🗣️ 情景例句
first thing in the morning.
这是我明天早上的第一件事。
It's nothing. Don't mention it.
区区小事，何足挂齿。
Yes, I've looked for it everywhere, said Han Meimei.
“是的，我到处都找过了，”韩梅梅说。