1、The applicant must have been a lawful permanent resident for five years. During these five years, the applicant should be physically present in the United States for at least half of that time.

2、If the applicant takes trips outside the United States, he must not be absent from the U.S. for a continuous period of more than one year. If there has been an absence of more than one year, it would break the continuity of the physical presence requirement. Also, if the applicant did not obtain a reentry permit to remain outside the U.S. for more than one year, his lawful permanent residence status may be deemed abandoned.

3、Generally speaking, the applicant must be a person of good moral character during the five-year or three-year residency period. However, the examiner from the Bureau of Citizenship & Immigration Service (formerly known as the Immigration & Naturalization Service) may take into account of the applicant’s earlier acts and conduct beyond the five-year or three-year residency period, if such acts and conduct are relevant in determining the applicant’s present moral character. Giving false testimonies to obtain an immigrant benefit and certain criminal convictions, including but not limited to, murder, aggravated felonies, prostitution, and crimes involving moral turpitude or controlled substance are examples of acts that lack good moral character. However, waivers and exceptions are available for certain convictions.

4、The applicant must be 18 years old.

5、The applicant must demonstrate an elementary level of reading, writing, and understanding of the English language and U.S. history. The English requirement shall not apply to (a) persons who are over 50 years of age and have resided in the U.S. for 20 years since becoming permanent residents, or (b) persons who are over 55 years of age and have been residing in the U.S. for 15 years since becoming permanent residents. These two groups of applicants however, are still required to take the history exam in their own native language.