Yes, this. I'm American but have cumulatively spent several years in India -- mostly Delhi, with about 6 months in Ahmedabad -- over the past couple of decades.

Yes, this. I'm American but have cumulatively spent several years in India -- mostly Delhi, with about 6 months in Ahmedabad -- over the past couple of decades. It's given me the the ability to comprehend (but not really speak) basic "chaste" Hindi, with a bit of Gujarati on the side. In practical terms this is essentially meaningless, because most of the time, people are speaking several languages at once. Last night I was in a supermarket in London, listening to the staff who were animatedly speaking what I think was a mashup of Bhojpuri (some of which I could understand) and Malayalam (no chance). Was totally baffling. Elsewhere I've seen Salman Rushdie describe the language of Bombay as "HUG-ME": "Hindi Urdu Gujarati Marathi English", with the apparent objective being to cram words from all five languages into every sentence. He's not wrong. This will be one hell of an ML challenge.