U.S. permanent residents may qualify for U.S. citizenship after having been a permanent resident for the last three or five years (depending on which naturalization category they are applying under). Eligibility for U.S. citizenship will also depend on additional factors, including age, physical presence and continuous residence in the U.S., ability to read, write, speak and understand basic English, good moral character, and willingness to adopt the principles and ideals of the U.S. Constitution.