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Recently, I went to a city called Lille in France. Surprisingly enough I noticed that some people were using 'septante' and 'nonante' instead of the regular used ones in France. I thought this was only in Belgium, or is this because it's a border region (since Lille is very close to the Belgian border)? If so, where else does this occur?
And also, does everyone in France (and Canada f.e.) understand 'septante' and 'nonante'?