Once you get a green card to become a US citizen you need to have had the green card with continuous physical presence in US for minimum period of 5 years and above the age of 18 years. Using the US Immigration Form N-400 the naturalization process can be started end of which you will be given the citizenship certificate as proof that you are a US citizen.
Green Card and a US Passport will be enough for a person to re- enter the US. One thing to be noted here is the duration that one stays out of the US. If the person is away from the US for a year or longer, then a permit to reenter must be obtained. The applicant should have applied for the permit and got it approved before leaving the US itself.Form I-131 is used to apply for permit to reenter the US
"Permanent green card and you are ouside the US for more then one years and you want to back?"
Yes
To obtain a US Green Card to Japan, you would need to apply for permanent residency in the United States through a family member, employer sponsorship, investment, or other qualifying means. Once you have obtained a Green Card, you can then apply for a visa to live and work in Japan. It is important to research and understand the specific requirements and processes involved in obtaining both the Green Card and the visa for Japan.
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yes they can do that
First thing that one would require to become a US citizen is the Green Card. For that they need a sponsor. Once obtained a Green card, then they have to be a green card holder for 5 years ( 3 yrs for conditional residents). Third is maintaining a continuous residence in the US. They also need to be 18 yrs of age. Finally they must be able to speak, write and read normal English and have sufficient knowledge about the history of the US constitution.
Can you stay eight months out of US With green card ?
No. A green card is issued to foreign nationals residing in the US.
Yes
The process to get green card can be through marriage,employment or through relative and should be petitioned for by the US citizen or green card holder spouse, employer or US citizen relative or green card holder in US respectively. Depending on the availability of the visas under the category you apply the time period to get a green card changes.
If you are in the US with a green card and you get into trouble by fighting or anything else, they can retract your green card. If that happens, you will be deported back to your original country.