Ppf
[医][=pellagra preventive factor]抗糙皮病因子，维生素pp
🗣️ 情景例句
Those are you just need.
那正是你们所需要的。
I don't know. You may look in the TV Guide.
我不知道，你可以看看《电视报》。
good-tempered elephant who will give many years of loyal service.
脾气温顺、能忠实为人服务多年的大象。