Editing Japanese grammar (section)

====Open and closed classes====

The two [[inflection|inflected]] classes, verb and adjective, are historically considered [[closed class]]es, meaning they do not readily gain new members—but see the following paragraphs.<ref name="Uehara1998">{{cite book|last=Uehara |first=Satoshi|year= 1998|title= Syntactic categories in Japanese: a cognitive and typological introduction|publisher= Kurosio|series= Studies in Japanese linguistics|volume= 9|isbn=9784874241622}}</ref>{{rp|76}}<ref>{{cite journal |last1=Dixon |first1=R. M. W. |title=Where Have all the Adjectives Gone? |journal=Studies in Language |date=1 January 1977 |volume=1 |issue=1 |pages=19–80 |doi=10.1075/sl.1.1.04dix}}</ref>{{rp|48}} Instead, new and borrowed verbs and adjectives are typically conjugated [[periphrasis|periphrastically]] as verbal noun + {{transliteration|ja|suru}} (e.g. {{Nihongo3|do studying; study|勉強する|benkyō suru}}) and adjectival noun + {{transliteration|ja|na}}. This differs from [[Indo-European languages]], where verbs and adjectives are [[Open class (linguistics)|open classes]], though analogous "do" constructions exist, including English "do a favor", "do the twist" or French "faire un footing" (do a "footing", go for a jog), and periphrastic constructions are common for other senses, like "try climbing" (verbal noun) or "try parkour" (noun). Other languages where verbs are a closed class include [[Basque language|Basque]]: very few [[Basque verbs]] (albeits very common ones) have synthetic conjugation, all the others are only formed periphrastically. Conversely, pronouns are closed classes in Western languages but open classes in Japanese and some other [[East Asian languages]].

In a few cases historically, and much more commonly recently, new verbs are created by appending the [[suffix]] {{Nihongo3||〜る|-ru}} to a noun or using it to replace the end of a word. This is most often, but not exclusively, done with borrowed words, and results in a word written in a mixture of katakana (stem) and hiragana (inflectional ending), which is otherwise very rare.<ref>{{cite web |url=http://japaneselevelup.com/homage-to-るru-the-magical-verbifier/ |title=Homage to る(ru), The Magical Verbifier |date= 2011-07-18 |author=Adam|work=Japanese Level Up }}</ref> This is typically casual, with the most well-established example being {{Nihongo3|skip class; play hooky|[[:ja:サボる|サボる]]|sabo-ru}} (circa 1920), from {{Nihongo3|sabotage|サボタージュ|sabotāju}}, with other common examples including {{Nihongo3|write a memo|メモる|memo-ru}}, from {{Nihongo|memo|メモ}}, and {{Nihongo3|make a mistake|ミスる|misu-ru}} from {{Nihongo3|mistake|ミス|misu}}. In cases where the borrowed word already ends with or even contains a {{Nihongo3||ル|ru}} or {{Nihongo3||リ|ri}}, this may be [[Rebracketing|rebracketed]] as a verb ending and changed to a {{Nihongo3||る|ru}}, as in {{Nihongo3|to [[google (verb)|google]]|ググる|gugu-ru}}, from {{Nihongo3|Google|グーグル|gūguru}}; {{Nihongo3|to double|ダブる|dabu-ru}}, from {{Nihongo3|double|ダブル|daburu}}; and {{Nihongo3|to favorite (e.g. a [[Tweet (social media)|tweet]])|ファボる|fabo-ru>}}, from {{Nihongo3|favorite|ファボリート|faboriito}}.<ref>{{cite web |title =「ディスる」「タクる」は70%が聞いたことがないと回答 国語世論調査で判明|trans-title=70% of Japanese people have never heard of the words ''taku-ru'' and ''disu-ru''.  |url = http://nlab.itmedia.co.jp/nl/articles/1409/25/news148.html | access-date = 2016-01-20 }}</ref><ref>{{cite web|title=morphology - Characteristics of 'loan word root + る' verbs - Japanese Language StackExchange|url=https://japanese.stackexchange.com/questions/66495/characteristics-of-loan-word-root-%E3%82%8B-verbs|access-date=2025-01-27}}</ref> New verbs coined in this fashion are uniformly group 1 verbs and, at least in the Tokyo accent, consistently are stressed immediately before the final る.

New adjectives are extremely rare; one example is {{Nihongo3|yellow|黄色い|kiiro-i}}, from adjectival noun {{Nihongo3||黄色|kiiro}}, and a more casual recent example is {{Nihongo3|gross|きもい|kimo-i}}, by contraction of {{Nihongo3|bad-feeling|気持ち悪い|kimochi waru-i}}.<ref>[http://linguistics.stackexchange.com/questions/9012/languages-with-different-open-and-closed-word-classes Languages with different open and closed word classes]</ref> By contrast, in Old Japanese {{Nihongo3||〜しき|-shiki}} adjectives (precursors of present {{transliteration|ja|i}}-adjectives ending in {{Nihongo3||〜しい|-shi-i}}, formerly a different word class) were open, as reflected in words like {{Nihongo3|pitiful|痛々しい|ita-ita-shi-i}}, from the adjective {{Nihongo3|painful, hurt|痛い|ita-i}}, and {{Nihongo3|heavenly, sublime|神々しい|kō-gō-shi-i}}, from the noun {{Nihongo3|god|神|kami}} (with [[Rendaku|sound change]]). Japanese adjectives are unusual in being closed class but quite numerous – about 700 adjectives – while most languages with closed class adjectives have very few.<ref>''The Typology of Adjectival Predication,'' Harrie Wetzer, [https://books.google.com/books?id=ORUUwhdDPpUC&pg=PA311 p. 311]</ref><ref name="guide96">''The Art of Grammar: A Practical Guide,'' Alexandra Y. Aikhenvald, [https://books.google.com/books?id=XFBVBQAAQBAJ&pg=PA96 p. 96]</ref> Some believe this is due to a grammatical change of inflection from an aspect system to a tense system, with adjectives predating the change.

The [[Grammatical conjugation|conjugation]] of {{transliteration|ja|i}}-adjectives has similarities to the conjugation of verbs, unlike Western languages where inflection of adjectives, where it exists, is more likely to have similarities to the [[declension]] of nouns. Verbs and adjectives being closely related is unusual from the perspective of English, but is a common case across languages generally, and one may consider Japanese adjectives as a kind of [[stative verb]].

Japanese vocabulary has a large layer of [[Sino-Japanese vocabulary|Chinese loanwords]], nearly all of which go back more than one thousand years, yet virtually none of them are verbs or "{{transliteration|ja|i}}-adjectives" – they are all nouns, of which some are verbal nouns ({{transliteration|ja|suru}}) and some are adjectival nouns ({{transliteration|ja|na}}). In addition to the basic verbal noun + {{transliteration|ja|suru}} form, verbal nouns with a single-character root often experienced sound changes, such as {{Nihongo3||〜する|-suru}} → {{Nihongo3||〜ずる|-zuru}} ([[rendaku]]) → {{Nihongo3||〜じる|-jiru}}, as in {{Nihongo3|forbid|禁じる|kin-jiru}}, and some cases where the stem underwent sound change, as in {{Nihongo3|reach|達する|tassuru}}, from {{Nihongo3||達|tatsu}}.

Verbal nouns are uncontroversially nouns, having only minor syntactic differences to distinguish them from pure nouns like 'mountain'. There are some minor distinctions within verbal nouns, most notably that some primarily conjugate as {{Nihongo3||〜をする|-o suru}} (with a particle), more like nouns, while others primarily conjugate as {{Nihongo3||〜する|-suru}}, and others are common either way. For example, {{Nihongo3|to experience|経験をする|keiken o suru}} is much more common than {{Nihongo3||経験する|keiken suru}}, while {{Nihongo3|to pardon|勘弁する|kanben suru}} is much more common than {{Nihongo3||勘弁をする|kanben o suru}}.<ref>{{Cite web |url=http://aveneca.com/cbb/viewtopic.php?f=8&t=3855 |title=Closed and open classes in Natlangs (Especially Japanese) |access-date=February 22, 2015 |archive-url=https://web.archive.org/web/20150222070657/http://aveneca.com/cbb/viewtopic.php?f=8&t=3855 |archive-date=February 22, 2015 |url-status=dead }}</ref> Adjectival nouns have more syntactic differences versus pure nouns, and traditionally were considered more separate, but they, too, are ultimately a subcategory of nouns.

There are a few minor word classes that are related to adjectival nouns, namely the [[taru adjective|{{transliteration|ja|taru}} adjectives]] and [[naru adjective|{{transliteration|ja|naru}} adjectives]]. Of these, {{transliteration|ja|naru}} adjectives are fossils of earlier forms of {{transliteration|ja|na}} adjectives (the {{transliteration|ja|nari}} adjectives of [[Old Japanese]]), and are typically classed separately, while {{transliteration|ja|taru}} adjectives are a parallel class (formerly {{transliteration|ja|tari}} adjectives in [[Late Old Japanese]]), but are typically classed with {{transliteration|ja|na}} adjectives.