Desu and da

1. Say what something is with です

   〜は 〜です says that one thing is another: 私は 十五才です。 これは 私の かばんです。 です never changes, whether you mean I am, she is or they are, and it is the same for one thing or many.

2. Say what something is not with じゃありません

   Swap です for じゃありません to make the sentence negative: 私は 日本人じゃありません。 ではありません means the same and sounds more formal, so it suits letters and formal writing. Both are correct at either tier.

3. Talk about the past with でした

   でした is the past of です: きのうは 私の たんじょうびでした。 Use it whenever a time word points back, such as きのう, せんしゅう or きょねん.

4. Say what something was not with じゃありませんでした

   Add でした to the negative to put it in the past: じゃありませんでした, or ではありませんでした in formal writing. その 人は 先生じゃありませんでした。 means that person was not a teacher.

5. Join two facts with で

   To say two things about the same person or thing, change the first です to で: ゆきさんは 私の 友だちで、 日本人です。 で has no tense of its own, so the ending of the sentence decides whether you mean now or the past.

6. Leave out what is already clear

   Japanese drops words the listener already knows. Asked 学生ですか。, you can answer はい、 学生です。 with no 私は. Saying 私は in every sentence sounds heavy, so use it when you first bring yourself into the conversation.

7. Use the plain forms だ, じゃない, だった and じゃなかったHigher only

   Between friends and in a diary, です becomes だ: 今日は 休みだ。 The negative is じゃない (or ではない), the past だった and the past negative じゃなかった (or ではなかった). Keep です for adults and for formal tasks.

8. Use だ before と思いますHigher only

   Inside a longer sentence, a noun or a な-adjective takes だ before と思います: あしたは 雨だと 思います。 An い-adjective never takes だ, so it is 楽しいと 思います.

です

The polite word for is, am or are. It links a topic to what it is, and never changes for the person.

じゃありません and ではありません

Is not, am not or are not. ではありません is more formal and suits writing.

でした

Was or were: the past of です.

じゃありませんでした

Was not or were not. In formal writing, use ではありませんでした.

Linking で

The form of です that joins two facts about the same thing: 学生で、 十六才です.

Topic

What a sentence is about, marked by は. In 山田さんは 先生です, the topic is 山田さん.

Polite style

Speech and writing that end in です and ます, used with adults, with people you don't know well and in formal tasks.

だHigher only

The plain form of です, used with friends and family and in diaries. Its past is だった.

Plain styleHigher only

Casual speech and writing with だ and plain verb forms, used with friends.

• Making です negative by adding to it, as in ですじゃありません.

  じゃありません takes the place of です completely: 先生です becomes 先生じゃありません.

• Keeping です in a sentence about the past, as in せんしゅうは テストです.

  A past time word needs the past ending: せんしゅうは テストでした. Examiners treat a tense that clashes with its time word as an error that makes you hard to follow.

• Using です for there is, as in こうえんに 犬です for there's a dog in the park.

  For there is, use います (people and animals) or あります (things): こうえんに 犬が います. です says what something is.

• Using だ with an adult or in a formal task.Higher only

  だ is casual. With a teacher and in the formal writing task, end each sentence with です or でした.

More Words and sentences topics

• The core particles
• Adjectives and adverbs
• Asking questions
• Kosoado words
• More particles
• Numbers, dates and time

Keep reading

• What are the GCSE Japanese grade boundaries?
• The GCSE Japanese syllabus, explained