Mon-Khmer family is a big and elder languages family that is still represented by more than 90 languages and dialects distributed on a vast geographical zone from Burma to Vietnam.
Sanskrit is an Indo-Aryan language group that survives like literary and sacred language of Brahmanism (Old India).
Pali is an Indo-European language group related to Sanskrit, and that is still used nowadays as religious language by the Buddhists in Southern India, Sri Lanka, Burma and Thailand.