throwaway5778

Okay, the real trick is to find a method that works for you. People love to shower everyone with advice, especially now that the edtech industry is bubbling with the soaring of Duolingo et al., but from experience only two things are really proven to actually work for everyone:

-Spaced repetition

-Lots of exposure

That's it. The rest is up to you. Some people swear by their specific app, some people religiously study their Assimil handbook, some people will argue that you should never ever learn grammar, some people swear by total immersion, and Nassim Taleb (who speaks like 7+ languages including like Ancient Greek) just reads a lot of books, but ultimately little of it matters insofar as it does one of the above two. There's an overabundance of learning materials out there for you to grab and use, just have your pick and find what's best for you.

Oh, and it goes without saying, but like with all learning, or indeed all cognitively demanding tasks, you have to actually want to learn. Ideally there should be an external motivator that pushes you and from which you can feel rewarded as you learn, this can range from 'watching anime without subtitles' to 'speaking with your SO in their language' but it has to be something.

Your 2 years estimate is way too conservative, I've seen people do it in a year, sometimes a few months if the languages are close enough (French-Italian-Spanish-Portuguese etc.)

Then there are all the really intensive courses/immersion programs where failure is basically forbidden (FSI, DLI, French Foreign Legion) and people reach B2-C1 very quickly, even for 'hard' languages (like Japanese or Arabic for a native English speaker, or French for a native Chinese speaker).

Yeah people love to go on about brain plasticity but few people actually know much about it (for instance how you can re-induce said plasticity in adults), let alone how it relates to language learning as an adult.

>Also, your rebuttal does not consider the fraction of those adults who learned those languages when they were young.

That still includes:

-Pretty much all immigrants

-All populations using a regional lingua franca (Modern Standard Arabic, Swahili, Indonesian, French, English, Russian, Portuguese)

-Everyone who learned English as a requirement for their job (that's everyone in business, research, the tourism industry, the software industry and probably a few others I'm missing)

-Everyone who learned another language as part of their higher education (usually English, but can also include languages like French, German or Russian)

Of course the language acquisition is usually far from perfect. You probably won't get rid of your accent as an adult, and your writing may be rife with mistakes. But as a communication tool, most adults manage just fine, because communication is part of being human and humans are naturally good at communicating.

Seeing how the vast majority of adults does in fact speak two languages and a huge chunk of them even more (e.g. most of Africa) I'd say your initial premise (adults struggle to learn anything past one) is misguided.