typically omit subject pronouns even when there is no explicit expression of the subject. Many Pama–Nyungan languages, however, have clitics, which often attach to nonverbal hosts to express subjects. The other languages of Northwestern Australia are all pro-drop, for all classes of pronoun. Also, Papuan languages of New Guinea and Nilo-Saharan languages of East Africa are pro-drop. Among the indigenous languages of the Americas, pro-drop is almost universal, as would be expected from the generally polysynthetic and head-marking character of the languages. That generally allows eliding of all object pronouns as well as subject ones. Indeed, most reports on Native American languages show that even the emphatic use of pronouns is exceptionally rare. Only a few Native American languages, mostly language isolates (Haida, Trumai, Wappo) and the Oto-Manguean family are known for normally using subject pronouns. Yahgan, a critically endangered language isolate from Tierra del Fuego, didn't have any pro-drop when it was still spoken widely in the late 19th century, when it was first described grammatically and had texts translated into English and other languages (three biblical New Testament texts: Luke, John, and Acts of the Apostles). In fact, emphatic pronouns and cross-reference pronouns on the verb commonly appeared together. Pragmatic inference Classical Chinese exhibits extensive dropping not only of pronouns but also of any terms (subjects, verbs, objects, etc.) pragmatically inferable, giving a very compact character to the language. Note, however, that Classical Chinese was a written language, and such word dropping is not necessarily representative of the spoken language or even of the same linguistic phenomenon. See also (NSL) (NSP) – The parameter which determines if languages are pro-drop, marking them as either positive (+) or negative (-) NSP. ; many languages such as Arabic and Hebrew lack a "to be" verb which is implicit in the subject. References Further reading Bresnan, Joan (ed.) (1982) The Mental Representation of Grammatical Relations, MIT Press, Cambridge, Massachusetts. Chomsky, Noam (1981) Lectures on Government and Binding: The Pisa Lectures. Holland: Foris Publications. Reprint. 7th Edition. Berlin and New York: Mouton de Gruyter, 1993. Graffi, Giorgio (2001) 200 Years of Syntax. A critical survey, John Benjamins, Amsterdam, The Netherlands. Moro, Andrea (1997) The raising of predicates. Predicative noun phrases and the theory of clause structure, Cambridge Studies in Linguistics, Cambridge University Press, Cambridge, England. Rizzi, Luigi (1982) Issues in Italian Syntax, Foris, Dordrecht. Krivochen, Diego and Peter Kosta (2013) Eliminating Empty