Acetonide
丙酮化合物
??? 情景例句
Thanks for your understanding and cooperation.
謝謝你的理解和合作。
A friend is never known till a man have need.
不到患難時，永遠不能認識真正的朋友。
6 What would you like to be admired for?
6。你樂于被夸獎的事是什么？