主题：谁给解答一下"邮政用品"的定义

问题有一点儿太简单了,是吗?但我还就是拿捏不准^_^ 对于中文的"邮票"定义我知道相对的英文内容有:Stamp, Semi-Postal, Air Mail, Air Mail Special Delivery Stamps, Air Post Semi-Official Stamp (这里包括半官方发行的航空邮票), Registration, Postage Due, War Tax Stamp, Perforated Official stamp, Overprinted Official Stamp等等 对于"邮政用品"我知道的英文内容有:Postal Stationery, envelopes, special Order Envelopes, election envelopes, Regular and Special Order Letter Sheets, Post Bands and Wrappers, Air Letters, Post Cards, Letter Cards, Reply Letter Card, Formula Registered Envelopes, Formula Aerogramme等等 请哪位给出具体的定义说明,谢谢!