There’s different levels of “fluency”. Roughly summing up the CEFR[1] model:
A1: Can ask and answer simple questions
A2: Can hold simple conversations
B1: Can talk about interests or events
B2: Can understand the main ideas of more complex or subject-specific texts
C1: Can use language flexibly without much searching for expressions
C2: Can easily speak and comprehend virtually everything in the target language
C1 is probably what I’d consider fluency, and looking at my own peers and language, some adults don’t even fit the criteria for C2 in their own native language.
CEFR doesn’t entirely map to native language development well, since it assumes fluency in the speaker’s native tongue and a certain ability to grasp more complex topics in the firsts place, where a child would still have to develop the mental faculties.
Still, attempting to describe native language development in CERF, at age 5, children are expected to “have mastered all basic grammatical markers at this age and should be speaking in grammatically correct sentences most of the time”[2], which I would consider somewhere between A2 and B1.
If the mental development for fluency in your native language are present, I do think that comprehensive immersion in a target language for five years, supported by helpful natives, can bring you a long way to fluency. The Goethe-Institute estimates that learning German will take approximately 600-750 hours[3] to reach C1, though it bases that estimate on its own dedicated language courses. Investing an average 3h of learning the language per week for five years would put you at 780. With additional support and practice outside of lessons, I think you could do with much less than that.
There’s different levels of “fluency”. Roughly summing up the CEFR[1] model:
A1: Can ask and answer simple questions
A2: Can hold simple conversations
B1: Can talk about interests or events
B2: Can understand the main ideas of more complex or subject-specific texts
C1: Can use language flexibly without much searching for expressions
C2: Can easily speak and comprehend virtually everything in the target language
C1 is probably what I’d consider fluency, and looking at my own peers and language, some adults don’t even fit the criteria for C2 in their own native language.
CEFR doesn’t entirely map to native language development well, since it assumes fluency in the speaker’s native tongue and a certain ability to grasp more complex topics in the firsts place, where a child would still have to develop the mental faculties.
Still, attempting to describe native language development in CERF, at age 5, children are expected to “have mastered all basic grammatical markers at this age and should be speaking in grammatically correct sentences most of the time”[2], which I would consider somewhere between A2 and B1.
If the mental development for fluency in your native language are present, I do think that comprehensive immersion in a target language for five years, supported by helpful natives, can bring you a long way to fluency. The Goethe-Institute estimates that learning German will take approximately 600-750 hours[3] to reach C1, though it bases that estimate on its own dedicated language courses. Investing an average 3h of learning the language per week for five years would put you at 780. With additional support and practice outside of lessons, I think you could do with much less than that.
[1] Wikipedia: Common European Framework of Reference for Languages, https://en.wikipedia.org/wiki/Common_European_Framework_of_Reference_for_Languages, accessed 2024-09-02
[2] Speech and Language for Kids: 5-Year-Old Speech Checklist, https://www.speechandlanguagekids.com/what-speech-and-language-skills-should-my-5-year-old-have/, accessed 2024-09-02
[3] Goethe-Institut: Frequently Asked Questions, Section “Our Courses”, Question “How long does it take to learn German?”, https://www.goethe.de/ins/gb/en/m/sta/lon/kur/faq.html#accordion_toggle_6206750_2, accessed 2024-09-02