system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: why can kids pick up a new language and speak it like a native with no accent but adults cannot?

Assuming an equal amount of language immersion as a 10 year old who moves to a new country, why can't a 30 year old pick up the language to the same extent?
gpt
Human beings have what is described in linguistics as a language acquisition device, wherein exposure to language before puberty, will result in a native tongue; after puberty the mastering of inflection within the language is rarely successful and certainly not easy. This is what we were taught in linguistics at university anyway.