Editing Japanese language (section)

===Inflection and conjugation===
Japanese nouns have no grammatical number, gender or article aspect. The noun {{Nihongo||本|hon}} may refer to a single book or several books; {{Nihongo||人|hito}} can mean "person" or "people", and {{Nihongo||木|ki}} can be "tree" or "trees". Where number is important, it can be indicated by providing a quantity (often with a [[Japanese counter word|counter word]]) or (rarely) by adding a suffix, <!--example? meaning "hito-tachi" and "mono-domo"?--> or sometimes by duplication (e.g. {{Nihongo2|人人}}, {{tlit|ja|hitobito}}, usually written with an iteration mark as {{Nihongo2|人々}}). Words for people are usually understood as singular. Thus ''Tanaka-san'' usually means ''Mx Tanaka''. Words that refer to people and animals can be made to indicate a group of individuals through the addition of a collective suffix (a noun suffix that indicates a group), such as ''-tachi'', but this is not a true plural: the meaning is closer to the English phrase "and company". A group described as ''Tanaka-san-tachi'' may include people not named Tanaka. Some Japanese nouns are effectively plural, such as ''hitobito'' "people" and ''wareware'' "we/us", while the word ''tomodachi'' "friend" is considered singular, although plural in form.

Verbs are [[Japanese conjugation|conjugated]] to show tenses, of which there are two: past and non-past, which is used for the present and the future. For verbs that represent an ongoing process, the ''-te iru'' form indicates a continuous (or progressive) [[grammatical aspect|aspect]], similar to the suffix ''ing'' in English. For others that represent a change of state, the ''-te iru'' form indicates a perfect aspect. For example, ''kite iru'' means "They have come (and are still here)", but ''tabete iru'' means "They are eating".

Questions (both with an interrogative pronoun and yes/no questions) have the same structure as affirmative sentences, but with intonation rising at the end. In the formal register, the question particle ''-ka'' is added. For example, {{Nihongo3|"It is OK"|いいです|ii desu}} becomes {{Nihongo3|"Is it OK?"|いいですか。|ii desu-ka}}. In a more informal tone sometimes the particle {{Nihongo||の|-no}} is added instead to show a personal interest of the speaker: ''Dōshite konai-no?'' "Why aren't (you) coming?". Some simple queries are formed simply by mentioning the topic with an interrogative intonation to call for the hearer's attention: ''Kore wa?'' "(What about) this?"; {{tlit|ja|O-namae wa?}} ({{Nihongo2|お名前は？}}) "(What's your) name?".

Negatives are formed by inflecting the verb. For example, {{Nihongo3|"I will eat bread" or "I eat bread"|パンを食べる。|Pan o taberu}} becomes {{Nihongo3|"I will not eat bread" or "I do not eat bread"|パンを食べない。|Pan o tabenai}}. Plain negative forms are ''i''-adjectives (see below) and inflect as such, e.g. {{Nihongo3|"I did not eat bread"|パンを食べなかった。|Pan o tabenakatta}}.

The so-called ''-te'' verb form is used for a variety of purposes: either progressive or perfect aspect (see above); combining verbs in a temporal sequence (''Asagohan o tabete sugu dekakeru'' "I'll eat breakfast and leave at once"), simple commands, conditional statements and permissions (''Dekakete-mo ii?'' "May I go out?"), etc.

The word ''da'' (plain), ''desu'' (polite) is the [[Copula (linguistics)#Japanese|copula]] verb. It corresponds to the English verb ''is'' and marks tense when the verb is conjugated into its past form ''datta'' (plain), ''deshita'' (polite). This comes into use because only ''i''-adjectives and verbs can carry tense in Japanese. Two additional common verbs are used to indicate existence ("there is") or, in some contexts, property: ''aru'' (negative ''nai'') and ''iru'' (negative ''inai''), for inanimate and animate things, respectively. For example, ''Neko ga iru'' "There's a cat", ''Ii kangae-ga nai'' "[I] haven't got a good idea".

The verb "to do" (''suru'', polite form ''shimasu'') is often used to make verbs from nouns (''ryōri suru'' "to cook", ''benkyō suru'' "to study", etc.) and has been productive in creating modern slang words. Japanese also has a huge number of compound verbs to express concepts that are described in English using a verb and an adverbial particle (e.g. ''tobidasu'' "to fly out, to flee", from ''tobu'' "to fly, to jump" + ''dasu'' "to put out, to emit").

There are three types of adjectives (see [[Japanese adjectives]]):
# {{Nihongo2|形容詞}} {{tlit|ja|keiyōshi}}, or ''i'' adjectives, which have a [[Japanese conjugation|conjugating]] ending {{Nihongo||い|i}}. An example of this is {{Nihongo krt|"to be hot"|暑い|atsui}}, which can become past ({{Nihongo2|暑かった}} {{tlit|ja|atsukatta}} "it was hot"), or negative ({{Nihongo2|暑くない}} {{tlit|ja|atsuku nai}} "it is not hot"). ''nai'' is also an ''i'' adjective, which can become past (i.e., {{Nihongo2|暑くなかった}} {{tlit|ja|atsuku nakatta}} "it was not hot").
#: {{Nihongo2|暑い日}} {{tlit|ja|atsui hi}} "a hot day".
# {{Nihongo2|形容動詞}} {{tlit|ja|keiyōdōshi}}, or ''na'' adjectives, which are followed by a form of the [[Copula (linguistics)|copula]], usually ''na''. For example, ''hen'' (strange)
#: {{Nihongo2|変な人}} {{tlit|ja|hen na hito}} "a strange person".
# {{Nihongo2|連体詞}} {{tlit|ja|rentaishi}}, also called true adjectives, such as ''ano'' "that"
#: {{Nihongo2|あの山}} {{tlit|ja|ano yama}} "that mountain".

Both ''keiyōshi'' and ''keiyōdōshi'' may [[Predicate (grammar)|predicate]] sentences. For example,

<blockquote><poem>{{Nihongo2|ご飯が熱い。}} {{tlit|ja|Gohan ga atsui.}} "The rice is hot."
{{Nihongo2|彼は変だ。}} {{tlit|ja|Kare wa hen da.}} "He's strange."</poem></blockquote>

Both inflect, though they do not show the full range of conjugation found in true verbs.
The ''rentaishi'' in Modern Japanese are few in number, and unlike the other words, are limited to directly modifying nouns. They never predicate sentences. Examples include ''ookina'' "big", ''kono'' "this", ''iwayuru'' "so-called" and ''taishita'' "amazing".

Both ''keiyōdōshi'' and ''keiyōshi'' form [[adverb]]s, by following with ''ni'' in the case of ''keiyōdōshi'':

<blockquote>{{Nihongo2|変になる}} {{tlit|ja|hen ni naru}} "become strange",</blockquote>

and by changing ''i'' to ''ku'' in the case of ''keiyōshi'':

<blockquote>{{Nihongo2|熱くなる}} {{tlit|ja|atsuku naru}} "become hot".</blockquote>

The grammatical function of nouns is indicated by [[Adposition|postposition]]s, also called [[Japanese particles|particles]]. These include for example:

* '''{{Nihongo2|が}} {{tlit|ja|ga}}''' for the [[nominative case]]. 
: {{Nihongo2|'''彼が'''やった。}} {{tlit|ja|'''Kare ga''' yatta.}} "He did it."
* '''{{Nihongo2|を}} {{tlit|ja|o}}''' for the [[accusative case]]. 
: {{Nihongo2|'''何を'''食べますか。}} {{tlit|ja|'''Nani o''' tabemasu ka?}} "'''What''' will (you) eat?"
* '''{{Nihongo2|に}} {{tlit|ja|ni}}''' for the [[dative case]].
: {{Nihongo2|'''田中さんに'''あげて下さい。}} {{tlit|ja|'''Tanaka-san ni''' agete kudasai}} "Please give it '''to Mx Tanaka'''."
: It is also used for the [[lative case]], indicating a motion to a location.
: {{Nihongo2|'''日本に'''行きたい。}} {{tlit|ja|'''Nihon ni''' ikitai}} "I want to go '''to Japan'''."
* However, '''{{Nihongo2|へ}} {{tlit|ja|e}}''' is more commonly used for the lative case.
: {{Nihongo2|'''パーティーへ'''行かないか。}} {{tlit|ja|'''pātī e''' ikanai ka?}} "Won't you go '''to the party'''?"
* '''{{Nihongo2|の}} {{tlit|ja|no}}''' for the [[genitive case]],<ref>{{Cite journal |last=Vance |first=Timothy J. |date=April 1993 |title=Are Japanese Particles Clitics? |journal=[[Japanese Language and Literature|Journal of the Association of Teachers of Japanese]] |volume=27 |pages=3–33 |doi=10.2307/489122 |jstor=489122 |number=1}}</ref> or nominalizing phrases.
: {{Nihongo2|'''私の'''カメラ。}} {{tlit|ja|'''watashi no''' kamera}} "'''my''' camera"
: {{Nihongo2|スキーに行く'''の'''が好きです。}} {{tlit|ja|Sukī-ni iku '''no''' ga suki desu}} "(I) like go'''ing''' skiing."
* '''{{Nihongo2|は}} {{tlit|ja|wa}}''' for the topic. It can co-exist with the case markers listed above, and it overrides ''ga'' and (in most cases) ''o''.
: {{Nihongo2|'''私は'''寿司がいいです。}} {{tlit|ja|'''Watashi wa''' sushi ga ii desu.}} (literally) "'''As for me''', sushi is good." The nominative marker ''ga'' after ''watashi'' is hidden under ''wa''.

Note: The subtle difference between '''''wa''''' and '''''ga''''' in Japanese cannot be derived from the English language as such, because the distinction between sentence topic and subject is not made there. While ''wa'' indicates the topic, which the rest of the sentence describes or acts upon, it carries the implication that the subject indicated by ''wa'' is not unique, or may be part of a larger group.

<blockquote>''Ikeda-san '''wa''' yonjū-ni sai da.'' "As for Mx Ikeda, they are forty-two years old." Others in the group may also be of that age.</blockquote>

Absence of ''wa'' often means the subject is the [[focus (linguistics)|focus]] of the sentence.

<blockquote>''Ikeda-san '''ga''' yonjū-ni sai da.'' "It is Mx Ikeda who is forty-two years old." This is a reply to an implicit or explicit question, such as "who in this group is forty-two years old?"</blockquote>