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I think some people can achieve those levels, but it's not very common. I've talked to college instructors with studies in linguistics and they talked about studies related to coordinate bilinguals.
Maybe google-ing you can find more info about that.
If the non-native speaker learns the second language as an adult, that person may achieve native rated fluency, but the pronunciation of the second language will never be as perfect as a native speaker.
If the second language (or even third) is learned as a child, fluency and perfect pronunciation can be expected.
And the only way to achieve real fluency in a second language, is to live in a place where that second language is spoken. One can never achieve real fluency merely by academic instruction.
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