Pronouns and possessive forms

How to make possessive forms of pronouns and regular nouns:

Pronouns we memorize, though you do see some patterns throughout:

• I = நான்; my=என்
• you = நீ ; your = உன்
• you (polite or plural) = நீங்கள், your= உங்கள்
• we (exclusive)= நாங்கள், our=எங்கள்
• we (inclusive)= நாம், our= நம்
• he/his அவன்/இவன்;  theirs = அவர்கள்/இவர்கள்
• she/her அவள்/இவள்;  theirs = அவர்கள்/இவர்கள்
• he/she/his/her அவர்/இவர்;  theirs = அவர்கள்/இவர்கள்
• it (close, here)= இது; its=இதன்; theirs (neuter)=இவைகளுடைய
• it (far, over there)=அது; its=அதன்; theirs (neuter)= அவைகளுடைய

Regular and proper nouns seem to have two options:
Add the suffix "oodaya" or "in"
above we see that "it" uses "ளுடைய"
other examples: house= வீடு; house's = வீடின்
I am currently in the polling stage to find what the rules are.
When do you use "in" and when "oodaya"???
Are they essentially synonymous?

Possessive/Genitive form is expected in chapter 5 of Hart's Tamil for Beginner's though it is introduced without much explanation, and the accompanying grammar book does not have a section for it...
In Asher's Colloquial Tamil "ooda" is used to designate the possessive form: "peeraasiriyar professor; peeraasiriyaroo∂a professor’s."

Index of Tamil Noun Cases

Noun Cases in Tamil: வேற்றுமை  
In Tamil, noun cases are added to the end of a noun to indicate what in English often is a preposition "in" "on" "with" etc. General information links are provided immediately below, followed by more specific links to posts related to each Noun Case. Updated as more posts are written.

• This link to the Tamil Language Online has a brief overview of the Case suffixes.
• My post on Tamil Pronouns in each of the Noun Cases
• Howard Schiffman's article on The Tamil Case System

 The Tamil names for the cases are essentially "first case" "second case" etc. Not very descriptive! And it seems like different books have the cases in different orders, so don't memorize "second case" etc. just yet!
Nominative case - முதல்வேற்றுமை/ எழுவாய்வேற்றுமை - use the regular noun
Objective/Accusative case/Direct Object  - இரண்டாம் வேற்றுமை  - ஐ ending.  The exact rules depend on the ending vowel of the noun.

• Present Tense and Direct Object, Lessons 2-3 from the Duke pdf, briefly covers direct object
  
• Direct Object and Present Tense, Lesson 5 exercises from the Duke pdf
• Direct Objects of nouns ending in டு /று Lesson 7 from the Duke pdf
• Direct Objects of nouns ending in short vowels, Lesson 8 from the Duke pdf
  

Instrumentive - மூன்றாம் வேற்றுமை -
Dative case -நான்காம் வேற்றுமை  -உக்கு/-க்கு ending

• Formation of the Indirect Object/Dative Case Exercises from Lessons 20-22 of the Duke pdf

Ablative - ஐந்தாம் வேற்றுமை -
Possessive (sometimes called genitive) ஆறாம் வேற்றுமை

• Pronouns and possessive forms 

Locative  ஏழாம் வேற்றுமை
Vocative எட்டாம் வேற்றுமை , விளி வேற்றுமை
Sociative - -

The term for case endings in general: வேற்றுமையுருபு