Pentafluorination
五氟化反应
🗣️ 情景例句
What are the best exercises for my health?
什么是最利于我身体健康的锻炼方式？
We used to have a lot of fun when we were that age.
当我们是变老时，我们过去常有很多趣事。
You two seem to know each other.
你们俩似乎认识。