surface mail

名词 surface mail:

1. mail that is sent by land or sea

1. It's2 yuan by surface mail and3.6 yuan by air.
   寄平信2元，寄航空要3元6角。
2. By surface mail?
   普通邮递吗？
3. Surface mail or air mail?
   普通邮件还是航空邮件？
4. It take about two weeks to go surface mail from here to London.
   普通邮件从这儿寄往伦敦要花两个星期左右时间。