So how long would it take for a native English speaker to learn Hindi?, surely not 10 bloody years and still remain uncomfortable enough to communicate in it.
The Foreign Service Institute of the US Department of State has a list based on data gathered on the average number of hours required to learn different languages. The list of languages are divided into three main groups depending on the relative difficulty for a NATIVE English speaker to learn them, some languages are more closer to English and thus require less time than others, although this is just a rough guide and not an absolute measure.
Category 1 are "languages are closely related to English", these are French, Germain, Italian.. roughly 23-24 weeks (575-600 class hours)
Category 2 are "languages with significant linguistic and/or cultural differences from English" - Greek, Turkish, Farsi, Hindi, Russian, Tamil etc... 44 weeks (1100 class hours)
Category 3 are the hardest for native English speakers, they are Arabic, Mandarin, Cantonese, Korean etc... 88 weeks (2200 class hours)(about half that time preferably spent studying in-country)
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