Polyfluorocarbon
[化] 多氟烃; 多氟代烃
🗣️ 情景例句
(a foreigner) Is that a special day?
（一个外国人）是一个特殊的日子吗？
An old physician,and a young lawyer.
医生老的好，律师年轻的好。
When is the store closing?
这家店什么时候结束营业？