names, places, or individuals involved or as a topic of the conversation at hand are repeated more than one would think necessary.) Four factors are widely accepted for the use of referent language including (i) competition with a possible referent, (ii) salience of the referent in the context of discussion (iii) an effort for unity of the parties involved, and finally, (iv) a blatant presence of distance from the last referent. Referential expressions are a form of anaphora. They are also a means of connecting past and present thoughts together to create context for information at hand. Analyzing the context of a sentence and determining whether or not the use of referent expression is necessary is highly reliant upon the author/speaker's digression- and is correlated strongly with the use of pragmatic competency. Nonreferential uses of language Silverstein's "Pure" Indexes Michael Silverstein has argued that "nonreferential" or "pure" indices do not contribute to an utterance's referential meaning but instead "signal some particular value of one or more contextual variables." Although nonreferential indexes are devoid of semantico-referential meaning, they do encode "pragmatic" meaning. The sorts of contexts that such indexes can mark are varied. Examples include: Sex indexes are affixes or inflections that index the sex of the speaker, e.g. the verb forms of female Koasati speakers take the suffix "-s". Deference indexes are words that signal social differences (usually related to status or age) between the speaker and the addressee. The most common example of a deference index is the V form in a language with a T–V distinction, the widespread phenomenon in which there are multiple second-person pronouns that correspond to the addressee's relative status or familiarity to the speaker. Honorifics are another common form of deference index and demonstrate the speaker's respect or esteem for the addressee via special forms of address and/or self-humbling first-person pronouns. An Affinal taboo index is an example of avoidance speech that produces and reinforces sociological distance, as seen in the Aboriginal Dyirbal language of Australia. In that language and some others, there is a social taboo against the use of the everyday lexicon in the presence of certain relatives (mother-in-law, child-in-law, paternal aunt's child, and maternal uncle's child). If any of those relatives are present, a Dyirbal speaker has to switch to a completely separate lexicon reserved for that purpose. In all of these cases, the semantico-referential meaning of the utterances is unchanged