and Vietnamese: Form a linguistic area based on the areal feature of phonemic tone distinctions. Indo-Aryan and Dravidian languages: Include the shared areal feature of retroflex consonants. Chipewyan, Cree, French, and English: Phonological convergence of c and s-series consonants. Standard Average European - the convergence of several European languages, both Indo-European and unrelated ones See also Dialect levelling Linguistic divergence Maltese language Mixed language Sprachbund References External links The Convergence Project Language contact