Seeing as I've studied Asian languages for a hella time, I rather just move to the other country and study it there. Takes way too long if you don't live next door.
If you want to be lazy, choose your neighboring countries language.
This would be french and spanish for americans. Some Canadian speak french, some mexicans spanish.
These two languages can be brought over seas also.
Mandarin Chinese is probably isolated somewhat, except in America cause we have tons of different people here. However for those who don't live in melting pot cities, learning a language without the speakers of the language around you is hard and will often cause one to fail quickly when they go to the destination where the language is mainly used. A thing with Asian languages is that sometimes people create slang and their areas will use the language differently. It's very complex learning Asian languages, that's why I stopped and decided to go back to just learning Science for now.
By the way, I studied Nihongo.
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The tones can become annoying. That's why I spent a lot of time watching videos, anime, online T.V.
jref.com and japantoday.com have a whole forum built on learning the Japanese language (Nihongo) Supposedly Mandarin is more difficult than Japanese and if that's the case, I would move to China, but people can't move to china because they have too many people, so moving next door might help. Heck, learning russian might not be a bad idea.
Last I remember China took over part of russia so if you learn russian, you could move over near China and learn Chinese while you're in russia.
However Russia itself is a difficult language because of the characters, however they are somewhat closely related to english and probably takes less time to work out than Japanese.
