there is none mentioned in the constitution of India. [A] Dude I think u just didnt do ur schooling right? Do U have doubt about it... I think even a 2nd Std student can google it out. anyhow Fun apart.
I agree one can definately put an attempt to learn not only kannada but the number of lnaguage he/she wish to learn. I would rather put ur sentence in a right way " People should learn regional language so that who doesnt know our National language Hindi or english " can do conversation with them too.
To justify on my first comment, I found ur comments baseless". so wrote my first comment.
Never the less I really dont feel that anyone in a domacratic country has a right to force anything to anyone. Be it a poet or anyone, People should realize what they should do and if they feel they should implement. Unless and until your words does harm anyone, any lnaguage is great and we have our national lanugage so that people who migrate from Bengal to Delhi or Hyd to Tamil can use them. Rest all language to learn will strngthen ur skills.