明天就要开长途去休斯顿办护照和旅行证了，昨天在ＵSPS买了2份回邮信封，是那种
first class mail，邮票大概$5，但忘记了网上这样写的：
“申请回邮服务的，须在递交申请时提供预付邮资的UPS(AIR ONLY)或USPS的EXPRESS
MAIL回邮信封（寄件人和收件上地址栏均填写申请人姓名和地址）”
请问有经验的能确认一下ＵSPS的first class mail可以吗，还是＊只能＊ＵPS的air
mail 或ＵSPS的express mail？
谢谢！
s******y 发帖数: 540
2
ＵSPS的express mail ONLY, and you have to put stamp on the
envelope. I heard somebody asked the same question when I was
there last week.
