我在网上查过后发现中文英文网站info差不多。以下这段话比较有代表性。没有再在除您网站之外的地方看见类似practice。所以想请问您，这种长期签证是在提交I-407表格时也要申请的，还是他们自动给？如果是申请怎么申请？填什么表格？要把护照寄去么？ 谢谢！
-Your mother has to get the green card officially (interview pass does not mean she have got the green card), then she can provide the completed I-407 to the US Consulate in China (if she is in China) and at the same time she can apply for the B2 visa immediately (or anytime later). Thus,the visa office may offer her a B2 visa with multiple entries for multiple years (e.g. 10 years) validity. How many years of the B2 visa validity depends on the visa officer persoanl decision, no requirement by law.
如果是申请怎么申请？填什么表格？要把护照寄去么？
-Provide the complete I-160 (complete it online) as everyone does, then mkae appointment and then, interview just like your mother did before. Of course, your mother can apply for the B2 visa at the same by providing all the documents for the B2 visa application when she gives up the green card.
