回複：美國移民局如何知道你逾期居留？

沒想明白美國移民局沒有出關口，如何知道你逾期居留？ 為什麽那些“黑“人一旦出境，就沒可能再入境呢？
-From your I-94. When your I-94 expires, your are逾期居留. If you leave U.S. without providing the the I-94 to the airlines/CBP and you want to enter U.S. again after the I-94 expires for 6 months, the CBP will ban you to enter U.S. no matter whether you leave U.S. before the I-94 expires or not. That is why people always provide the I-94 to the ailrine/CBP to tell tthe CBP that they leave U.S. without unlawful presence/before the I-94 expires.