Belonging to them

उनका

English Usage: Their car is parked outside.

Hindi Usage: उनकी कार बाहर पार्क है।

Used to describe something that belongs to multiple people or things

उनका

English Usage: I appreciate their effort in the project.

Hindi Usage: मैं प्रोजेक्ट में उनके प्रयास की सराहना करता हूँ।