です is a polite sentence-ending word that links a subject with a description, often translated as "is," "am," or "are" in English. It is not a verb for existence, and is used to make sentences polite and complete when ending with a noun or adjective.
Structure:
- [A] は [B] です → "[A] is [B]"
Used with:
- Nouns: わたしは がくせい です。
- Na-adjectives: このまちは しずか です。
- I-adjectives: さむいです。(polite tone only, not required)
- Don’t use です after verbs (e.g., ❌たべますです)
- I-adjectives don’t require です, but you can add it for politeness
わたしは学生です。
Watashi wa gakusei desu.
I am a student.
これはほんです。
Kore wa hon desu.
This is a book.
そのいぬはしずかです。
Sono inu wa shizuka desu.
That dog is quiet.
The copula です changes based on tense (present/past) and polarity (affirmative/negative). Below are the standard polite forms:
| Form | English | Romaji |
|---|---|---|
| Present Positive | "is / am / are" | desu |
| Present Negative | "is not" | janai desu / dewa arimasen |
| Past Positive | "was" | deshita |
| Past Negative | "was not" | janakatta desu / dewa arimasen deshita |
- じゃないです is more casual than ではありません
- Stick to one politeness level per sentence
これはほんじゃないです。
Kore wa hon janai desu.
This is not a book.
わたしは学生でした。
Watashi wa gakusei deshita.
I was a student.
それはにんじんじゃなかったです。
Sore wa ninjin janakatta desu.
That was not a carrot.
The copula in Japanese changes depending on formality and politeness. While the meaning remains similar (“is / am / are”), the tone and setting differ.
| Politeness | Form |
|---|---|
| Casual | だ (da) |
| Polite | です (desu) |
| Very Polite | でございます (degozaimasu) |
- Don’t mix だ and です in the same sentence unless you understand nuance
- でございます is rare in casual conversation but common in service and formal settings
彼は先生だ。
Kare wa sensei da.
He is a teacher. (casual)
彼は先生です。
Kare wa sensei desu.
He is a teacher. (polite)
わたくしは田中でございます。
Watakushi wa Tanaka de gozaimasu.
I am Tanaka. (very polite)