各位老师好， 我先生因工作需要经常回国出差，大概每两个月回国一次，每次停留 2 到4 周。我和孩子在美国，我们已有绿卡两年，之前都没有问题，这次入关在护照上被标注 I-407 advised。
请问：
1。 如果下次出差（工作需要回国出差），需要申请什么文件？是否要申请re-entry permit？
-Yes, he needs to file I-131 for reentry permit. Otherwise his green card may have a problem if he uses to travel again. Form I-407 is "Abandonment of Lawful Permanent Resident Status". The note of "I-407 advised" which the CBP officer left on his passport is for the next CBP officer your spouse faces when entering the country again. In short - the CBP officer doesn't think your spouse wants to live US permanently, but think he is just using his green card as a "border crossing card".
2。怎样证明是在美国居住？公司证明，房屋证明，子女上学证明和税表等， 是否这些可以证明在美国居住，从而让CBP取消 I-407 advised被注？
-Just file I-131 to apply for the reentry permit to travel again and he will be fine.
