How long does it take to learn a completely unfamiliar language through full immersion without any common language or previous contact.

Question

You sometimes hear accounts of sailors, missionaries, anthropologists and such who go to live among people with entirely foreign languages. If there is no common language how long is it likely to take to learn. I recall hearing about a guy by the name of Jack Renton who was a castaway who lived among the Lau at first as a slave but later marrying into them. By the end he apparently knew their language well. Is there any research or accounts on how long this process might take in such a situation where there is no common tongue and what it involves that you could direct me to?. How quickly (weeks months years) is it likely to take to make progress and what factors might be important. Asking as research for a story I am writing. Sorry if this isn't the right place.

Answer 1

Firstly, it depends on which language it is and it depends on your propensity to learn. On average, if you are fully immersed in a language (speaking and hearing nothing but that language and being forced to communicate) then around 5-7 months to be fluent enough. So for languages like Dutch, Danish, French and Italian, about 7 months (575 hours) is about average. However if that language is Cantonese or Arabic you are looking at nearly 2 years or 2,200 hours of study. There is also a difference in the level of language. Most people after being immersed for about 3 months can get by conversationally, but to learn and conduct business (especially if that is technical or scientific) you need superior proficiency which takes far longer.

There are cases of immigrants who move to Europe or the USA and learn a foreign language very quickly if they have to go to school and learn, but I cannot think of any specific examples.