Question by Simmy: What happens to the language acquisition device after the critical period of learning?
If there is a language acquisition device in the human brain, why is there a critical period for learning a language? What happens to the LAD after the age of 6? Why don’t we remain able to easily acquire language?

Best answer:

Answer by Derek R
While I think it’s easier to acquire proficiency in childhood, acquiring fluency in adulthood is entirely possible. The majority of the world’s population today, for perhaps the first time in history, is multilingual. Did they all larn their second language in childhood? No, but it might have been easier

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