The Copula “Desu”

In this lesson, you'll learn about one especially important verb, desu, and how to use it as part of your first sentence structure.

Recommended background:

Politeness and Formality in Japanese – so that you know what it means to use polite/formal speech.

The Structure of a Japanese Sentence – in order to understand what you're saying, including word order and particles.

The Topic Marker “Wa” – mainly the first half, covering the concept of "topic" vs subject.

What is a Copula?

A copula is essentially a verb meaning "to be". It can be used to show identity (Max is a dog), properties (furry), state (happy), and membership in a set (one of my pets). Other verbs, like "become", "seem", "feel", and "appear", also function much like the main copula.

Forms of "be" English include "is", "am", "are", "was", "were", "been", and "being". The Japanese copula also has several forms, the most important of which are the plain form だ "da" and the polite form です "desu".

Note that while the English "to be" can also be used to show existence (I am in my living room), Japanese has two separate verbs for this purpose: いる "iru" for animate objects (animals, people, robots) and ある "aru" for inanimate objects. You'll learn how to use these verbs later on.

Using "Desu"

Although the Japanese copula is a somewhat unusual verb, it goes at the end of the sentence just like every other.

ほんだ。 Hon da. (It) is (a) book.

Note: I realize this sounds like a certain Japanese car manufacturer, but that Honda (本田) comes from the name of the company's founder.

Politeness shows up in the main verb (always the last in the sentence), which in this case is the copula, so in polite speech (teineigo) da is replaced with desu.

ほんです。 Hon desu. (It) is (a) book.

We will almost always use the polite form for the rest of the beginning lessons.

As a root verb, desu is non-past ("present") tense and affirmative ("positive"). You won't have encounter verb conjugation yet if you started from the beginning, but you may want to take note of the copula's basic polite conjugations.

Basic Conjugations of "Desu"
  Affirmative Negative
Non-past です desu では ありません de wa arimasen
Past でした deshita では ありませんでした de wa arimasen deshita

Being a rather unusual verb, the copula has an irregular conjugation in both its plain and polite forms. Fortunately, almost all other Japanese verbs are regular, in that they follow a universal conjugation pattern.

You'll learn more about verb conjugation later on. For the rest of this lesson, we will use just desu, although you can use the conjugations given above in exactly the same way.

As a side note, desu is believed to be a contraction of "de gozaimasu", which is now mainly used in keigo (honorific speech). At some point, the negative forms of gozaimasu were also replaced by the negative forms of arimasu.

Missing Inflections

Did you notice how I've been using "non-past" instead of "present"? This is because Japanese doesn't differentiate between present and future tenses. If the time frame is not specified separately, (now, soon, 3 years from now), then it must be inferred.

Japanese verbs also do not inflect for number (singular/plural), gender (male/female), or person (I/you/he), so as long as you want non-past tense, simply desu is the correct form to use.

Your First Sentence Structure

To say that something "is" something, you use the following sentence structure:

Hiragana A は B です。
Rooma-ji [A] wa [B] desu.
Partial. Trans. As for [A], (it) is [B].

Translation: [A] is/am/are [B].


わたしは たなかです。 Watashi wa Tanaka desu. I'm Tanaka.
これは ほんです。 Kore wa hon desu. This is a book.
たなかさんは にほんじんです。 Tanaka-san wa Nihonjin desu. Tanaka is a Japanese person. (=Tanaka is Japanese.)
ほんは えほんです。 Hon wa ehon desu. The book is a picture book.


[A] is the topic of the sentence, which can be any noun (person/animal/object/place/concept). This is specified with the topic marker "wa", and in this case of this sentence structure, the topic is generally also the subject.

[B] is also a noun, generally an identity of some sort, whether it be the exact identity of the entity in question (like a name) or a group it belongs in (like nationality). Japanese nouns do not inflect to show that they are plural, and do not take articles (a/an/the).

(Read more about nouns)

Adjectives are used in a way that looks deceptively similar to this pattern, but there is a subtle difference.

(Read more about adjectives)

Incomplete Sentences

Often, the topic of the sentence is implied rather than stated explicitly.

いとうです。 Itou desu. (I) am Itou.
えんぴつです。 Enpitsu desu. (It) is (a) pencil.

In the first example it's watashi "I" – simple enough. But what about the second? Japanese doesn't really have a word for "it", but if the topic was stated it would probably be kore "this".

The topic of a sentence is usually omitted if it is clear from context. This could be the case if the speaker is answering a question about the topic of the previous sentence, or it might simply be obvious, such as when introducing yourself or pointing to something. Because of this habit, translations out of context often ambiguous.

Expanding on "Wa" and "Desu"

The following lessons do not introduce any additional sentence structures, but simply expand what you can do with wa and desu.

And in the next step, we'll add in questions and sentence ending particles.

You'll then learn about adjectives and compound sentences, followed by verbs and conjugation.

Words to Remember

Hiragana Rooma-ji Class English
~は wa particle [topic marker]
です desu copula is/am/are
わたし watashi pron. I/me
これ kore pron. this, this one

Further Reading

Conjugations of the Japanese Copula

What Next?

Nouns, Pronouns, and Plurals

Questions and Negation

Counting in Japanese

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