Your evidence must be an original or certified copy”，所以问你这个怎么提供，后来找到：
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Born Outside the United States?
U.S. Citizenship at Birth
If you were born outside the United States and acquired U.S. citizenship through your U.S. citizen parent(s), please submit the following with your passport application:
- Your foreign birth certificate listing your parent(s)
- Your parent(s)’ evidence of U.S. citizenship
- Your parents' marriage certificate, if applicable
- A statement from your U.S. citizen parent(s) detailing all periods and places of their residence or physical presence in the United States and abroad before your birth.
