We talked about a genuine difficulty faced by speakers of Malayalam while learning the phonetically alien language of English,
here. This post is on yet another genuine difficulty with Malayalam, the reasons for which are entirely within the language.
While conversing in Malayalam, almost anyone will repeatedly face peculiar and severe problems with second person pronouns - there is no minimal and complete set of words which could be used in the sense of the single English word 'you' or for the complete triple of {tu, tum, aap} of Hindi (by completeness, one means that the set of words given can cover all situations where one addresses another person; One can address anybody from a kid to a venerable old man as 'you' in English). Malayalam has the words: "nee", "ningal", "thaangal", "angu", "thaan", "nammal", "iddeham", "saar", "madam" (and many more) which all CAN mean 'you' in various conversational contexts. And (this is the weird part!) even this gargantuan set is woefully incomplete. It has no words for addressing in second person, for instance, one's own parents!
To break free from this peculiar trap created by themselves, Mallus often use (1)the the relationship one has with the second person (2)or the proper name of the second person itself or (3) in some special cases, the profession of the socond person (doctor or teacher especially) as substitute for the straightforward 'you'. For instance, I ask my pop: "Did father like my blog?" where 'father' is a substitute for 'you'. Old friend and fellow-Mallu
Anand can tell ME (directly) something like(hopefully!): "I liked Nandakumar's post on the second person" where what he means is "I liked YOUR post...". This runs into difficulties when the 'you' in question is say, self's father, an elder who cannot be addressed by HIS name. Then 'you' becomes 'Nandakumar's father'. Needless to say, this does not solve the problem fully since the 'you' is defined with reference to something else - such a trick can often fail. So some folks bring in words like 'uncle', 'brother' and so on...as substitutes for 'you' - the problem keeps getting shifted, never solved.
Having watched the evolution of this language as a practitioner for so many years, one could recommend Governmental action to sort this out. Perhaps it could begin at primary schools where kids could be taught to address their teacher as 'thaangal' (the 'polite' you) and not ask questions like "What is teacher's name?". But it won't be easy at all; most Mallus find the word "thaangal" very awkward indeed! The wish for a single 'you' in Malayalam is unlikely to be ever fulfilled.
Historically, Kerala society was a very stratified one and in such a setting, a blanket 'you' for anybody could not have evolved. Indeed there used to be very deferential words 'you', as there were for 'I' as well: "adiyan", "eeyullavan",... (and the pompous practice of referring to self in plural). Modernization has largely eliminated many of these oddities but the second person difficulties persist.
One can see a clear link between prevalence of equality and the usage of a single second person pronoun, in Kerala. For instance, it is not surprising, given their substantial contribution to social equality, that the communists have a single word 'comrade' for any 'you' as long as the second person is also a commie. To give another example, at the Sabarimala temple (a rather odd place for the genuine equality prevalent there) one can address anybody as 'swami'. These are of courese sectarian solutions for a larger problem; and they can't help you address your parents!
Probably, one could again wonder: The rest of Indian society was equally stratified in olden times. How did only the Mallu fall into this weird 'second person trap'. There could be more complex reasons.