回複:請問各位關於I-94 and I-20的問題。 多謝各位!
Any non-immigrant in US should have I-94, but I-20 is specifically for non-immigrants in F-1 status besides their I-94s.
http://blog.wenxuecity.com/blogview.php?date=200709&postID=13250
http://blog.wenxuecity.com/blogview.php?date=200804&postID=4128