Ppf
[医][=pellagra preventive factor]抗糙皮病因子，维生素pp
🗣️ 情景例句
a two-bedroom house in Mount Kisco.
一栋有两间卧室的房子， 在Mount Kisco。
Henry got a toothache and asked to be excused.
亨利牙疼，请求离开一下。
We practise entrances and exits.
我们排练登场和退场。