PPabbr.包裹邮递（=Parcel Post)abbr.过去分词（=past participle）abbr.邮资付讫的(=postpaid)n.一种中文文件交换软件和通讯软件PPRn.生产零件分开出售

1. The cat is the origin of infection which the arch polypite gets sick.
   猫是弓形虫体病的传染源。