回复：回复：what is 绿卡章?

when your I-485 is approved, you will receive a notice from USCIS to tell you that your application is approved and you will receive your greencard (it is actually no long green) in certain time (usually 3 to 6 months). before you receive your official greencard, you could go to your local USCIS office to have your passport stamped. basically it is just a red stamp stating your application for permanent resident was approved and you're authorized to work legally in US. you may leave and come back the States with this stamp and it could be used as a work permit, too.