A is B. / A は B です。

How to say “A is B.” in Japanese

In English, be verb should be changed according to the subject. But in Japanese, there is no variant of ～は～です。
So simply you can explain A=B, using AはBです。

“は” is a topic marker that is added after the topic word.
Topics or subjects are most omitted in Japanese sentences when it is obvious from the context.

“は” is pronounced “wa” in this case.

“～” means wildcard. This part contains one or more words.
“。” is “.”(period).

Examples

私わたしはさとしです。

I am Satoshi.

私わたし [pronoun] I

彼かれは学生がくせいです。

He is a student.

彼かれ [pronoun] he
学生がくせい [noun] student

In Japanese, in many cases, we don’t distinguish singular or plural.
Only when we dare to emphasize the plural, we can add たち, ら or something(depends on the target) after the word. For example, “they” is 彼ら, “students” is 学生たち e.t.c.

彼女かのじょはアメリカ人じんです。

She is an American.

彼女かのじょ [pronoun] She
アメリカ人じん [noun] American

さとしさんはポケモントレーナーです。

Mr Satoshi is a Pokémon trainer.

～さん [suffix] Mr./Ms.

です can be replaced with だ(impolite) or である(story style).

If you emphasize the subject, は should be replaced with が. But you should not use が when the complement is not obvious from the previous context.

炭次郎たんじろうといいます。

©吾峠呼世晴／集英社・アニプレックス・ufotable

I am Tanjiro.

In Japanese, in the case the subject is obvious from the situation or previous context, the subject is almost omitted. It is unnatural not to omit the subject.

～といいます [compound] (I) say (my name is) ～
～と申もうします [compound] (I) say (my name is) ～ *more polite style

In the case of self-introduction, there are some more formal expressions like below. Of cause ～は～です is no problem, it is simple and not rude. The grammatical explanation is a little complicated, so I will omit it here.

Vocabulary

Pronouns

Japanese	Pronunciation	English	Note
私わたし	watashi	I	95% omitted
あなた	anata	you	65% omitted and 30% one’s name to talk with is used instead
彼かれ	kare	he	also means boyfriend
彼女かのじょ	kanojo	she	also means girlfriend
これ	kore	this	pointing to something close to you
それ	sore	it	pointing to something close to the person you are talking to
あれ	are	that	pointing to something far away

Occupations

Japanese	Pronunciation	English
学生がくせい	gakusei	student
先生せんせい	sensei	teacher, instructor, professor, doctor
医者いしゃ	isha	doctor, physician
弁護士べんごし	bengoshi	lawyer, counsel
警察官けいさつかん	keisatsukan	policeman, police officer
店員てんいん	teein	clerk, salesperson
会社員かいしゃいん	kaishain	office worker, company employee
エンジニア	enjinia	engineer
運転手うんてんしゅ	untenshu	driver, operator, chauffeur
料理人りょうりにん	ryoorinin	cook, chef
歌手かしゅ	kashu	singer, vocalist

Suffix words (about person)

Japanese	Pronunciation	English	Note
～さん	～san	Mr./Ms.	polite
～様さま	～sama	Mr./Ms.	more polite (often used in the business scene)
～先生せんせい	～sensee	prof./doc.	used for teacher, professor, doctor and author
～人じん	～jin	people	ex. アメリカ人 is American (people)
～人にん	～nin	people	a number of peaple
～歳さい	～sai	years old	–
～才さい	～sai	years old	a simplified version of Kanji
～年生ねんせい	～nensee	grader	ex. 1年生 is a first grader

Practice

Translate the following sentences into Japanese using the “AはBです。”.

How to say “She is Cute.” in Japanese

She is cute.

かわいい [I-adjective] cute, pretty, lovely, adorable

You have understood “A” can replace the subject of the sentence and “B” can replace the object of the sentence.
So “B” can replace not only nouns but I-adjective or Na-adjective.

Examples

たけしは大おおきい。

Takeshi is big.

大きい [I-adjective] large, generous, hefty

Add ”です” to the end of the sentence for a more polite expression. (たけしは大きいです。)

はるかは元気げんきだ。

Haruka is cheerful.

元気な [Na-adjective] cheerful, spry, vigorous, active, energetic

If the Na-adjective is at the end of the sentence, “な” should be transformed into “だ” or “です” at the end.
“です” is a more polite expression than “だ”. (はるかは元気です。)

Vocabulary

Japanese	Pronunciation	English	word class
かわいい	kawaii	cute, pretty, lovely, adorable	I-adjective
大おおきい	ookii	large, big	I-adjective
元気げんきな	genkina	cheerful, spry, vigorous, active, energetic	Na-adjective
親切しんせつな	sinsetsuna	kind, gracious, accommodating	Na-adjective

Click here for a detailed explanation of adjectives. [Under construction]

Practice

Translate the following sentences into Japanese using the “AはBです。”.

The Deeper Story of “A is B”

The grammatical structure of “A is B”

Role of “は”

Role of “は” no.1

・is a topic marker

e.g. Self-introduction

ゆきてぃです。

I am Yukitty.

In Japanese, modifiers are omitted as much as possible when they are obvious from the context or situation.
私は(I) is omitted. If not daringly omitted, it is emphasized.

Role of “は” no.2,3,4

・indicates contrast
・expresses the speaker’s thoughts
・indicates a choice of predicate

Role of “は” no.5

・used in a question sentence

Role of “は” no.6

・also represents the topic of the next sentence unless overwritten by a new topic marker

Role of “です” and “だ”

Role of “が”

Role of “が” no.1,2,3

・is a subject marker (for specific things/person)
・indicates a logical relationship
・indicates a choice of subject

Role of “が” no.4

・is used to report what the speaker noticed

Role of “が” no.5

・is used when the interrogative is the subject

Role of “が” no.6

・is used as a subject in a sub-sentence clause