Pentafluorination
五氟化反应
🗣️ 情景例句
When I say something, I mean it.
我说的一定会兑现。
He hasn't answered my letter yet.
他还没有给我回信。
Fine! I have a new watch. Do you like it?
很好，我有一块新手表，你喜欢它吗？