回复: I-94表要交回给美国海关吗?
http://www.uscis.gov/USCIS/About%20Us/Electronic%20Reading%20Room/Customer%20Service%20Reference%20Guide/NonimmigrantServices.pdf
What should I do if I forgot to turn in my I-94 when I left the U.S.?
Your departure from the U.S. was not recorded if you did not turn in your I-94 when you left. This can affect your eligibility to return.
You should send in your I-94. For information about where to send it and the evidence you should include to show when you left the U.S., we suggest you contact the U.S. Customs and Border Protection, which administers the process of people entering and exiting the U.S.
www.cbp.gov Their website is at
Or you can call them at either 202-354-1000 or 1-877-CBP-5511, Monday through Friday between 8:30 AM and 5:00 PM Eastern time.