The Proto-Indo-European language is the unattested, linguistic reconstruction common ancestor of the Indo-European languages, spoken by the Proto-Indo-Europeans.... , the hypothetical common ancestor of the Indo-European languages.
The Proto-Indo-Europeans were the speakers of the Proto-Indo-European language, and likely lived around 4000 BC, during the Copper Age and the Bronze Age, or possibly earlier, during the Neolithic or Paleolithic eras.... , the hypothetical speakers of the reconstructed Proto-Indo-European language.
