I came across this interesting article and agree with what it says.
Basically they're saying that not being surrounded by the context and culture of the language you're learning affects how fluently you speak the language.. pretty much common sense really! ;)
Pertinent quotes
- The findings could help explain why cultural immersion is the most effective way to learn a foreign tongue and why immigrants who settle within an ethnic enclave acculturate more slowly than those who surround themselves with friends from their new country
- Previous studies have shown that cultural icons such as landmarks and celebrities act like "magnets of meaning," instantly activating a web of cultural associations in the mind and influencing our judgments and behavior
Check it out!