Perfluorocarbon
全氟化碳
🗣️ 情景例句
Can you confirm that the meeting is at 9:00 a.m.?
你能否确认一下，开会的时间是早上9点吗？
One should travel out of his own country at least once.
我们至少应该离开自己的国度去旅行一次。
and of what had previously been wrong with his wife,
也不知道他妻子以前得的是什么病，