Ppf
[医][=pellagra preventive factor]抗糙皮病因子，维生素pp
🗣️ 情景例句
How long do you plan to stay with this company, if hired?
如果被雇佣，你打算在这家公司呆多久？
You should wear a heavy coat, It's below zero today.
你应该穿一件厚大衣，因为今天在零度以下。
In 1995, there was a very big race.
1995年举行了一次盛大的比赛。