How much is the American immigrant green card worth?

Hello, the American green card is a proof of permanent residence in the United States. Having a green card means having permanent residency, that is, foreigners who can stay in the United States for a long time. "Immigrating to the United States" means becoming a permanent resident of the United States. It has the following values:

1. American citizens can apply for relatives to immigrate to the United States.

2. Working in the federal government.

3. Engage in some special industries that only American citizens can do.

4. Citizenship cannot be revoked for almost a lifetime (the green card is likely to be revoked after the holder leaves the United States for a long time).

5. Elected and elected representatives of public opinion (members).

6. Serving in wartime and being protected by the United States overseas (American permanent residents are occasionally protected by the United States overseas, but it is not common and the intensity is small).

Hope to adopt thank you! The division of Canadian skilled immigrants from 30w, no charge for unsuccessful!