谢谢8老师。让我看到希望。
想知道从去美国领事馆，放弃自己的绿卡，申请B2签证，到最后进入美国，要多长时间？
-They can give up the green card and then apply for the B2 visa in the same day. The following website is for the green card abandonment:
http://guangzhou.usembassy-china.org.cn/abandonment-of-status.html
You can find such information in the website of any US Consulate in China.
Also more information:
http://www.immihelp.com/greencard/abandonment-greencard.html
因为曾经移民过，再申请非移民B2签证，有多大把握能申请下来？
-Should be fine as long as they show they have no immigration intent in this trip.
多谢！！！
