アメリカ合衆国にはいくつの種類の先住民族がある？
Native Americans, also known as American Indians, Indigenous Americans and other terms, are the indigenous peoples of the United States, except Hawaii. There are over 500 federally recognized tribes within the US, about half of which are associated with Indian reservations. The term "American Indian" excludes Native Hawaiians and some Alaska Natives, while Native Americans (as defined by the US Census) are American Indians, plus Alaska Natives of all ethnicities. Native Hawaiians are not counted as Native Americans by the US Census, instead being included in the Census grouping of "Native Hawaiian and other Pacific Islander".
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