Editing Relative clause (section)

===Strategies for indicating the role of the shared noun in the relative clause===
There are four main strategies for indicating the role of the shared noun phrase in the embedded clause.{{citation needed|date=May 2020}} These are typically listed in order of the degree to which the noun in the relative clause has been reduced, from most to least:

# Gap strategy or gapped relative clause
# Relative pronoun
# Pronoun retention
# Nonreduction

====Gapped relative clause====
In this strategy, there is simply a gap in the relative clause where the shared noun would go. This is normal in English, for example, and also in Chinese and Japanese. This is the most common type of relative clause, especially in [[subject–object–verb|verb-final]] languages with prenominal relative clauses, but is also widespread among languages with postnominal externally headed relative clauses.

There may or may not be any marker used to join the relative and main clauses. (Languages with a case-marked relative pronoun are technically not considered to employ the gapping strategy even though they do in fact have a gap, since the case of the relative pronoun indicates the role of the shared noun.) Often the form of the verb is different from that in main clauses and is to some degree nominalized, as in Turkish and in English [[reduced relative clause]]s.<ref>{{cite book | last=Carrol | first=David W. | edition=5th | title=Psychology of Language | publisher=Thomson & Wadsworth | location=Belmont | year=2008 |isbn=9780495099697 |oclc=144326346}}</ref><ref>{{cite book | last1=Townsend | first1=David J. |first2=Thomas G. |last2=Bever  | title=Sentence Comprehension: The Integration of Habits and Rules | year=2001 | publisher=MIT Press | location=Cambridge | pages=247&ndash;9 |oclc=45487549}}</ref>

In non-verb-final languages, apart from languages like [[Thai language|Thai]] and [[Vietnamese language|Vietnamese]] with very strong politeness distinctions in their grammars{{Citation needed|date=December 2011}}, gapped relative clauses tend, however, to be restricted to positions high up in the accessibility hierarchy. With obliques and genitives, non-verb-final languages that do not have politeness restrictions on pronoun use tend to use pronoun retention. English is unusual in that ''all'' roles in the embedded clause can be indicated by gapping: e.g. "I saw the person who is my friend", but also (in progressively less accessible positions cross-linguistically, according to the ''[[accessibility hierarchy]]'' described below) "...&nbsp;who I know", "...&nbsp;who I gave a book to", "...&nbsp;who I spoke with", "...&nbsp;who I run slower than". Usually, languages with gapping disallow it beyond a certain level in the accessibility hierarchy, and switch to a different strategy at this point. [[Classical Arabic]], for example, only allows gapping in the subject and sometimes the direct object; beyond that, a resumptive pronoun must be used. Some languages have no allowed strategies at all past a certain point—e.g. in many [[Austronesian languages]], such as [[Tagalog language|Tagalog]], all relative clauses must have the shared noun serving the subject role in the embedded clause. In these languages, relative clauses with shared nouns serving "disallowed" roles can be expressed by [[passive voice|passivizing]] the embedded sentence, thereby moving the noun in the embedded sentence into the subject position. This, for example, would transform "The person who I gave a book to" into "The person who was given a book by me". Generally, languages such as this "conspire" to implement general relativization by allowing passivization from ''all'' positions — hence a sentence equivalent to "The person who is run slower than by me" is grammatical. Gapping is often used in conjunction with case-marked relative pronouns (since the relative pronoun indicates the case role in the embedded clause), but this is not necessary (e.g. Chinese and Japanese both using gapping in conjunction with an indeclinable complementizer).

====Relative pronoun type====
This is a type of gapped relative clause, but is distinguished by the fact that the role of the shared noun in the embedded clause is indicated indirectly by the case marking of the marker (the [[relative pronoun]]) used to join the main and embedded clauses. All languages which use relative pronouns have them in clause-initial position: though one could conceivably imagine a clause-final relative pronoun analogous to an adverbial subordinator in that position, they are unknown.

Some languages have what are described as "relative pronouns" (in that they agree with some properties of the head noun, such as number and gender) but which do not actually indicate the case role of the shared noun in the embedded clause. [[Classical Arabic]] has "relative pronouns" which are case-marked, but which agree in case with the ''head'' noun. Case-marked relative pronouns in the strict sense are almost entirely confined to [[Standard Average European|European languages]]{{Citation needed|date=August 2011}}, where they are widespread except among the [[Celtic languages|Celtic family]] and [[Indo-Aryan languages|Indo-Aryan family]]. The influence of Spanish has led to their adaption by a very small number of [[indigenous languages of the Americas|Native American languages]], of which the best known are the [[Keresan languages]].<ref>{{cite web|url=http://wals.info/languoid/lect/wals_code_aco|title=WALS Online - Language Acoma|website=wals.info|access-date=8 April 2018}}</ref>

====Pronoun retention type====
In this type, the position relativized is indicated by means of a [[personal pronoun]] in the same syntactic position as would ordinarily be occupied by a noun phrase of that type in the main clause—known as a ''[[resumptive pronoun]]''. It is equivalent to saying "The woman who I saw <u>her</u> yesterday went home". Pronoun retention is very frequently used for relativization of inaccessible positions on the accessibility hierarchy. In [[Persian language|Persian]] and [[Classical Arabic]], for example, resumptive pronouns are required when the embedded role is other than the subject or direct object, and optional in the case of the direct object. Resumptive pronouns are common in non-verb-final [[languages of Africa]] and Asia, and also used by the Celtic languages of northwest Europe and [[Romanian language|Romanian]] ("Omul pe care <u>l</u>-am văzut ieri a mers acasă"/"The man who I saw <u>him</u> yesterday went home"). They also occur in deeply embedded positions in English, as in "That's the girl that I don't know what <u>she</u> did",<ref name="mckee">{{citation|title=Resumptive Pronouns in English Relative Clauses|first1=Cecile|last1=McKee|first2=Dana|last2=McDaniel|journal=Language Acquisition|volume=9|number=2|year=2001|pages=113–156|doi=10.1207/s15327817la0902_01|s2cid=143402998}}.</ref> although this is sometimes considered non-standard.

Only a very small number of languages, of which the best known is [[Yoruba language|Yoruba]], have pronoun retention as their sole grammatical type of relative clause.

====Nonreduction type====
In the nonreduction type, unlike the other three, the shared noun occurs as a ''full-fledged noun phrase'' in the embedded clause, which has the form of a full independent clause. Typically, it is the head noun in the main clause that is reduced or missing. Some languages use relative clauses of this type with the normal strategy of embedding the relative clause next to the head noun. These languages are said to have ''internally headed'' relative clauses, which would be similar to the (ungrammatical) English structure "[You see the girl over there] is my friend" or "I took [you see the girl over there] out on a date". This is used, for example, in [[Navajo language|Navajo]], which uses a special relative verb (as with some other Native American languages).

A second strategy is the ''correlative''-clause strategy used by [[Hindi]] and other [[Indo-Aryan languages]], as well as [[Bambara language|Bambara]]. This strategy is equivalent to saying "Which girl you see over there, she is my daughter" or "Which knife I killed my friend with, the police found that knife". It is "correlative" because of the corresponding "which ... that ..." demonstratives or "which ... she/he/it ..." pronouns, which indicate the respective nouns being equated. The shared noun can either be repeated entirely in the main clause or reduced to a pronoun. There is no need to front the shared noun in such a sentence. For example, in the second example above, Hindi would actually say something equivalent to "I killed my friend with which knife, the police found that knife".

Dialects of some European languages, such as Italian, do use the nonreduction type in forms that could be glossed in English as "The person just passed us by, she introduced me to the chancellor here."

In general, however, nonreduction is restricted to verb-final languages, though it is more common among those that are [[head-marking language|head-marking]].