An immigrant can become a US citizen either by birth or through Naturalization. Naturalization is generally referred to as the procedure through which a person not born in the United States voluntarily becomes a U.S. Citizen. Immigrants who wish to get US citizenship should file Form N 400, Application for Naturalization.
Who Can File N-400 Form for Citizenship?
You need to meet certain eligibility requirements before filing form N 400. You should be 18 years or older and a permanent resident (Green Card holder) now and during all of the past 5 years. You must reside in the United States for a continuous period before filing the naturalization application. If you are not married to an American citizen, you should reside in the U.S. for a continuous period of five years after admission to the U.S. as a permanent resident. If you are married to a U.S. citizen, you must reside in the U.S. for a continuous period of three years following admission to the U.S. as a permanent resident.
A prolonged absence from the U.S. will break the continuity of your residence in the U.S. for naturalization purposes. However, it may not affect your ability to return to the U.S. as a permanent resident. An absence from the U.S. of less than six months does not break your continuity of residence in the U.S. for naturalization purposes. However, if you are absent from the U.S. for a period of six months or more it breaks the continuity of your residence. If the break is between six months and one year, the break can be excused if a reasonable explanation can be given for your absence (e.g. overseas employment). If the break is for over a year, the continuity of your residence can be preserved and the break excused, if steps are taken prior to your trip abroad to preserve the residence and if you meet certain qualifications.
Additionally, you should have met your physical presence requirements too. It means that you have actually been in the United States. Mostly, you must be physically present in the United States for a certain number of months to be eligible for naturalization. Prior to applying, you should have resided in your current state for at least 3 months. It is the state where you are submitting the application for naturalization
Most importantly, you should not have broken any immigration law and you should not have been ordered to leave the United States. You should also prove at least 5 years of good moral character. In order to file Form N 400, you should take an English language test and a Civics test. Generally, form N 400 applicants must establish to the satisfaction of the interviewing officer that they are able to read, write and speak basic English and that they have basic knowledge of US history and government. If you have a medically determinable physical or mental impairment, where it affects your ability to learn English and Civics, you can be exempted. And finally you should be prepared to take an oath of allegiance to the United States.