我們在芝加哥，有點遠。我兒子準備坐火車或汽車去Buffalo,然後出入境。請問原來的i94卡處理有什麽不同，by land和by air出入境美國？
-Give the I-94 to the US CBP officer (美國海關官員) when he leave US if he travels to Canada by train or car. If by air, he just needs to give the I-94 to the airlines (the airlines then will forward the I-94 information to the CBP officer).
Thanks!!
