Ppf
[医][=pellagra preventive factor]抗糙皮病因子，维生素pp
🗣️ 情景例句
It's almost ten o'clock.
差不多十点了。
Do you think it looks good on me?
你看我穿着好看吗？
sank with all flags flying----in the harbour of the birth.
带着全身飘扬的彩旗，沉没在了它诞生的港口。