Editing Japanese grammar (section)

====Topic, theme, and subject: {{lang|ja|は}} {{transliteration|ja|wa}} and {{lang|ja|が}} {{transliteration|ja|ga}}====
{{see also|topic and comment}}
The complex distinction between the so-called topic, {{nihongo||は|wa}}, and subject, {{nihongo||が|ga}}, particles has been the theme of many doctoral dissertations and scholarly disputes.{{Citation needed|date=November 2021}} The clause {{nihongo||象は鼻が長い|zō-wa hana-ga nagai}} is well known for appearing to contain two subjects. It does not simply mean "the elephant's nose is long", as that can be translated as {{nihongo||象'''の'''鼻'''は'''長い|zō-'''no''' hana-'''wa''' nagai}}. Rather, a more literal translation would be "(speaking of) the elephant, its nose is long"; furthermore, as Japanese does not distinguish between singular and plural the way English does, it could also mean "as for elephants, their noses are long".

Two major scholarly surveys of Japanese linguistics in English, clarify the distinction.<ref>{{cite book |last=Shibatani |first=Masayoshi |date=1990b |title=The languages of Japan |place=Cambridge |publisher=Cambridge University Press}} {{ISBN|0-521-36070-6}} (hbk); {{ISBN|0-521-36918-5}} (pbk).</ref><ref name="Kuno1973">{{cite book |last=Kuno |first=Susumu |date=1973 |title=The structure of the Japanese language |place=Cambridge, MA |publisher=MIT Press |isbn=0-262-11049-0}}</ref> To simplify matters, the referents of {{transliteration|ja|wa}} and {{transliteration|ja|ga}} in this section are called the ''topic'' and ''subject'' respectively, with the understanding that if either is absent, the grammatical topic and subject may coincide.

As an abstract and rough approximation, the difference between {{transliteration|ja|wa}} and {{transliteration|ja|ga}} is a matter of focus: {{transliteration|ja|wa}} gives focus to the action of the sentence, i.e., to the verb or adjective, whereas {{transliteration|ja|ga}} gives focus to the subject of the action. However, when first being introduced to the topic and subject markers {{transliteration|ja|wa}} and {{transliteration|ja|ga}}, most are told that the difference between the two is simpler. The topic marker, {{transliteration|ja|wa}}, is used to declare or to make a statement. The subject marker, {{transliteration|ja|ga}}, is used for new information, or asking for new information.

=====Thematic {{transliteration|ja|wa}}=====
{{see also|Topic marker#Japanese: は}}
The use of {{transliteration|ja|wa}} to introduce a new theme of discourse is directly linked to the notion of grammatical theme. Opinions differ on the structure of discourse theme, though it seems fairly uncontroversial to imagine a first-in-first-out hierarchy of themes that is threaded through the discourse. However, the usage of this understanding of themes can be limiting when speaking of their scope and depth, and the introduction of later themes may cause earlier themes to expire.{{explain|date=November 2021}} In these sorts of sentences, the steadfast translation into English uses constructs like "speaking of X" or "on the topic of X", though such translations tend to be bulky as they fail to use the thematic mechanisms of English. For lack of a comprehensive strategy, many teachers of Japanese emphasize the "speaking of X" pattern without sufficient warning.

{{fs interlinear|lang=ja|indent=3
|ジョン は 学生 です。
|JON wa gakusei desu
|(On the topic of) John, (he) is a student.}}

A common linguistic joke shows the insufficiency of rote translation with the sentence {{nihongo||僕はウナギだ|boku wa unagi da}}, which per the pattern would translate as "I am an eel." (or "(As of) me is eel"). Yet, in a restaurant this sentence can reasonably be used to say "My order is eel" (or "I would like to order an eel"), with no intended humour. This is because the sentence should be literally read, "As for me, it is an eel," with "it" referring to the speaker's order. The topic of the sentence is clearly not its subject.

=====Contrastive {{transliteration|ja|wa}}=====
Related to the role of {{transliteration|ja|wa}} in introducing themes is its use in contrasting the current topic and its aspects from other possible topics and their aspects. The suggestive pattern is "X, but…" or "as for X, …".

{{fs interlinear|lang=ja|indent=3
|雨 は 降って います が…
|ame wa futte imasu ga…
|The rain is falling, but…}}

Because of its contrastive nature, the topic cannot be undefined.

{{fs interlinear|lang=ja|indent=3
|＊誰か は 本 を 読んで いる。
|*dareka wa hon o yonde iru
|*Someone is reading the book.}}

In this use, {{transliteration|ja|ga}} is required.

In practice, the distinction between thematic and contrastive {{transliteration|ja|wa}} is not that useful. There can be at most one thematic {{transliteration|ja|wa}} in a sentence, and it has to be the first {{transliteration|ja|wa}} if one exists, and the remaining {{transliteration|ja|wa}}s are contrastive. The following sentence illustrates the difference;<ref name="Kuno1973" />{{rp|48}}

{{fs interlinear|lang=ja|indent=3
|僕 が 知って いる 人 は 誰も 来なかった。
|boku ga shitte iru hito wa daremo konakatta
|(1) Of all the people I know, none came.<br>
(2) (People came but), there weren't any of the people I know.}}

The first interpretation is the thematic {{transliteration|ja|wa}}, treating {{nihongo|"the people I know"||boku ga shitte iru hito}} as the theme of the predicate {{nihongo|"none came"||dare mo konakatta}}. That is, if the speaker knows A, B, ..., Z, then none of the people who came were A, B, ..., Z. The second interpretation is the contrastive {{transliteration|ja|wa}}. If the likely attendees were A, B, ..., Z, and of them the speaker knows P, Q and R, then the sentence says that P, Q and R did not come. The sentence says nothing about A', B', ..., Z', all of whom the speaker knows, but none of whom were likely to come. In practice, the first interpretation is the likely one.

=====Exhaustive {{transliteration|ja|ga}}=====
Unlike {{transliteration|ja|wa}}, the subject particle {{transliteration|ja|ga}} nominates its referent as the sole satisfier of the predicate. This distinction is famously illustrated by the following pair of sentences:

{{fs interlinear|lang=ja|indent=3
|ジョンさん は 学生 です。
|Jon-san wa gakusei desu
|John is a student. (There may be other students among the people we're talking about.)}}

{{fs interlinear|lang=ja|indent=3
|(この グループ の 中 で) ジョン が 学生 です。
|(Kono gurūpu no naka de) Jon ga gakusei desu
|(Of all the people we are talking about) it is John who is the student.}}

The distinction between each example sentence may be made easier to understand if thought of in terms of the question each statement could answer. The first example sentence could answer the question:

{{fs interlinear|lang=ja|indent=3
|ジョンさん の 仕事 は 何 です か。
|Jon-san no shigoto wa nan desu ka
|What is John's occupation?}}

Whereas the second example sentence could answer the question:

{{fs interlinear|lang=ja|indent=3
|どちら の 方 が 学生 です か。
|Dochira no kata ga gakusei desu ka
|Which one (of them) is the student?}}

Similarly, in a restaurant, if asked by the waitstaff who has ordered the eels, the customer who ordered it could say:

{{fs interlinear|lang=ja|indent=3
|僕 が ウナギ だ。
|Boku ga unagi da
|The eels are for me (not these other people).}}

=====Objective {{transliteration|ja|ga}}=====
For certain verbs, {{transliteration|ja|ga}} is typically used instead of {{transliteration|ja|o}} to mark what would be the direct object in English:

{{fs interlinear|lang=ja|indent=3
|ジョンさん は フランス語 が 出来る。
|Jon-san wa furansu-go ga dekiru
|John knows French.}}

There are various common expressions that use verbs in English, often transitive verbs, where the action happens to a specific object: "to be able to do something", "to want something", "to like something", "to dislike something". These same ideas are expressed in Japanese using adjectives and intransitive verbs that describe a subject, instead of actions that happen to an object: {{nihongo|"to be possible"|出来る|dekiru}}, {{nihongo|"to be desired/desirable"|ほしい|hoshii}}, {{nihongo|"to be liked"|好きだ|suki da}}, {{nihongo|"to be disliked"|嫌いだ|kirai da}}. The equivalent of the English subject is instead the [[Topic–comment|topic]] in Japanese and thus marked by {{transliteration|ja|wa}}, reflecting the [[Topic-prominent language|topic-prominent]] nature of Japanese grammar.

Since these constructions in English describe an object, whereas the Japanese equivalents describe a subject marked with {{nihongo||が|ga}}, some sources call this usage of {{nihongo||が|ga}} the "objective ''ga''". Strictly speaking, this label may be misleading, as there is no object in the Japanese constructions.

As an example, the Japanese verb {{nihongo||分かる|wakaru}} is often glossed as transitive English verb "to understand". However, ''wakaru'' is an intransitive verb that describes a subject, so a more literal gloss would be "to be understandable".

{{fs interlinear|lang=ja|indent=3
|ジョンさん は 日本語 が 分かる。
|Jon-san wa nihongo ga wakaru.
|* John understands Japanese.  → translating into idiomatic English, using the transitive verb "to understand"<br>
<nowiki>*</nowiki> As for John, Japanese is understandable.  → translating more closely to the Japanese, with "Japanese" as the subject of an intransitive descriptive verb}}