Editing Function word (section)

==Overview==
Function words might be [[preposition]]s, [[pronoun]]s, [[auxiliary verb]]s, [[Grammatical conjunction|conjunctions]], [[Article (grammar)|grammatical articles]] or [[Grammatical particle|particles]], all of which belong to the group of [[closed class word|closed-class words]]. [[Interjection]]s are sometimes considered function words but they belong to the group of [[open class word|open-class words]]. Function words might or might not be [[Inflection|inflected]] or might have [[affix]]es.

Function words belong to the closed class of words in [[grammar]] because it is very uncommon to have new function words created in the course of speech. In the open class of words, i.e., nouns, verbs, adjectives, or adverbs, [[neologism|new words]] may be added readily, such as [[slang]] words, technical terms, and adoptions and adaptations of foreign words.

Each function word either: gives grammatical information about other words in a sentence or [[clause]], and cannot be isolated from other words; or gives information about the speaker's mental model as to what is being said.

Grammatical words, as a class, can have distinct [[phonological]] properties from content words. For example, in some of the [[Khoisan languages]], most content words begin with [[click consonant|clicks]], but very few function words do.<ref name="EB">{{Citation | last =Westphal | first =E.O.J. | contribution =The click languages of Southern and Eastern Africa | year =1971 | title =Current trends in Linguistics, Vol. 7: Linguistics in Sub-Saharan Africa | editor-last =Sebeok | editor-first =T.A. | place=Berlin | publisher =Mouton}}</ref> In English, very few words other than function words begin with the [[Pronunciation of English th|voiced ''th'']] [[voiced dental fricative|{{IPA|[ð]|cat=no}}]].<ref>{{cite journal |last1=Kelly |first1=Michael H. |title=Using sound to solve syntactic problems: The role of phonology in grammatical category assignments. |journal=Psychological Review |date=1992 |volume=99 |issue=2 |pages=349–364 |doi=10.1037/0033-295X.99.2.349 |url=https://psycnet.apa.org/doiLanding?doi=10.1037%2F0033-295X.99.2.349 |language=en |issn=1939-1471|url-access=subscription }}</ref> English function words may be spelled with fewer than [[three letter rule|three letters]]; e.g., 'I', 'an', 'in', while non-function words usually are spelled with three or more (e.g., 'eye', 'Ann', 'inn').

The following is a list of the kind of words considered to be function words with English examples. They are all [[uninflected word|uninflected]] in English unless marked otherwise:
*[[Article (grammar)|articles]] — ''the'' and ''a''. In some inflected languages, the articles may take on the case of the [[declension]] of the following noun.
*[[pronoun]]s — ''he'' :: ''him'', ''she'' :: ''her'', etc. — inflected in English
*[[adposition]]s — ''in'', ''under'', ''towards'', ''before'', ''of'', ''for'', etc. 
*[[conjunction (grammar)|conjunctions]] — ''and'' and ''but''
*[[subordinating conjunctions]] — ''if'', ''then'', ''well'', ''however'', ''thus'', etc.
*[[auxiliary verb]]s — ''would'', ''could'', ''should'', etc.  — inflected in English
*[[grammatical particle|particles]] — ''up'', ''on'', ''down''
*[[interjection]]s — ''oh'', ''ah'', ''eh'', sometimes called "filled pauses" 
*[[Expletive (linguistics)|expletives]] — take the place of sentences, among other functions.
*[[pro-sentence]]s — [[yes and no|''yes'', ''no'']], ''[[okay]]'', etc.