If you are a US citizen and got married to your fiancee, she can legally apply for her residency here in the United States even if she overstayed her student status. The process is called adjustment of status and she will need to submit the following forms after reading and following the instructions: I-485, I-130, G-325A, I-765, I-131, I-864. The total fee for the entire case is $1,490 ($1,070 I-485 + $420 I-130).
Answered on Mar 20th, 2013 at 2:20 PM