A common problem encountered while translating cinema scripts originally written in Hindi to other European languages is the use of 'you'. Many of Hindi movies are subtitled in European languages, but almost all of them are translated through English rather than from Hindi original. In English the word 'you' is used both for formal and informal address. A teacher calls his student 'hey you!' and a boy saying his teacher 'you are most welcome sir' is quite normal. There is nothing awkward when an owner of a small shop says his salesgirl, 'you should do evening duty today.' or 'you have been shifted to upper floor' and the salesgirl retorting, 'you can't change duties so whimsically, sir.'
But such language behaviour is totally unacceptable in India. Here, from the language point of view, people are stratified in three categories. A person could be called in three manners 'tu', 'tum' and 'aap' depending upon the situation. 'Tu', 'tum' and 'aap' are in increasing order of respect and formality. 'Tu' is the most informal or affectionate way of calling a person. School days pals will call each other as 'tu'. 'Tu kahan tha itne din', (where had you been these days?). Most European languages have their own version of informal and formal 'you'. In French, these distinctions are very important - you must understand when and why to use each of them. Otherwise, you may inadvertently insult someone by using the wrong 'you'.
In French Tu is the familiar you, which demonstrates a certain closeness and informality. tu is used when speaking to one friend, peer, colleague, relative, child, pet. Vous is the formal and plural 'you'. It is used to show respect or maintain a certain distance or formality with someone. Vous is used when speaking to someone you don’t know well, an older person, an authority figure, anyone to whom you wish to show respect. Vous is also the plural 'you' - it is used when talking to more than one person, closeness does not matter in that case. Same system is followed in Spanish (tú, usted), Russian (ti, voui), Italian (tu, lei) etc.

Now, the problem with two or three forms of 'you' is that in different cultures way of calling a person are different. Even within India itself, the way of addressing a person differs depending upon culture, language group, interaction with modernism etc. For example how would a husband address his wife or a wife would address her husband differs culture-wise.

Thus in a traditional Hindi speaking north Indian family a husband invariably calls his wife as 'tum', and the wife would call her hubby as 'aap' showing respect. Nothing surprising because in traditional India husband is to be treated as God by his wife. But in some language groups, for example Bengali, husband and wife call each other as 'tumi' the equivalent of 'tum' of Hindi. Even in a single language group there are several variants depending on the degree of their exposure to modernism. So even in Hindi language group we find urbanite, educated couples calling each other in more affectionate way.

Apart from home, at work also use of 'tum' and 'aap' is like a riddle for an outsider. Rustics call manual labourers with a degree of contempt using 'tu' and 'tum' without exception. While in urban India if the workers at lower rungs of the ladder like sweepers, peons, drivers happen to be the employees of governmental or big companies they may be addressed with a formal tone using 'aap'. In urban India a discovered sense of self-respect in these group have made them much sensitive on the issue of how they are addressed by others.

In small business a manager may address his subordinates as 'tum', but as the size of the business goes on increasing the distance between the supervisor and the subordinate also increases and thus changes the way of addressing a subordinate colleague.

Use of 'tu', 'tum' and 'aap' also varies according to area. Northern India's Haryana is famous for its informal way of talking. In India there is no dearth of scenes where a person from Bengal (claiming to be more cultured) grumbles on his not so close colleague from rustic Haryana addressing him as 'tum'.
Thus an understanding of proper cultural background is a must for somebody going to translate subtitles of an Indian film through the window of English.