Perfluorocarbon
全氟化碳
🗣️ 情景例句
The bridge is about three hundred and eighty-five feet long.
桥长约三百八十五英尺。
I'm serious.
我是说正经的。
Many of the stars cannot be seen because they are too far away.
许多星星我们之所以看不见，是因为它们离我们太远。