世界上很多事物,都是人类在生活实践中发明出来的。如我们现在寄递国际航空信件尚在使用的航空标签也是如此。当飞机问世后投入邮运不久,开始印制专用的航空邮票贴寄,以此加以区别。之后,各种邮票通用后,才在信封上加盖“航空”戳记来区分,随之世人发明了在航空邮件上加贴特定颜色的“航空”标签或使用专门的航空信封。 Many things in the world are invented by human beings in their life practice. The same is true of aviation labels that we are still using as we now send international airmail. Shortly after the launch of the aircraft into the postage, the printing of a dedicated air stamp was posted and sent for distinction. After that, after the stamps were common, they were marked with “aviation” stamps on the envelopes to distinguish them. Then the world invented to affix a special color “aviation” tag on airmail or use special aviation envelopes.