அவர

In a sentence

• அவருடைய பெயர் ரவி.

  His name is Ravi.

  Here, 'அவருடைய' is used as a possessive form to indicate ownership (his).

• நான் இன்று அவரை சந்தித்தேன்.

  I met him today.

  Here, 'அவரை' is used in the accusative case to refer to him (direct object of the verb).

• அவர்கள் பள்ளிக்குப் போகிறார்கள்.

  They are going to school.

  Here, 'அவர்கள்' is the plural form used to denote respect or as a pronoun for 'they' (subject of the sentence).