A person who was not born a U.S. citizen may acquire U.S. citizenship through a process known as naturalization.
Naturalization with the USCIS: The process immigrants have to go through to become citizens of the United States. A person may become a U.S. citizen by birth or through naturalization. Usually if children are Permanent Residents, they can derive citizenship from their naturalized parents. This is true whether is a child by birth or adoption. It is also possible to have your naturalization revoked.
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