Is, is it?, isn't

The pattern

です = is · ですか = is it? · じゃないです = isn't.

How they differ

です (desu) goes at the end of a polite sentence to say "X is Y." To ask, add か (ka): 「がくせい ですか?」(gakusei desu ka?) "Are you a student?" To say no, use じゃないです (ja nai desu): 「がくせい じゃないです。」(gakusei ja nai desu) "I'm not a student."

You'll often see:

は (wa): marks the topic → 「これは ペン です。」(kore wa pen desu)

Rising feel (or か) for questions; in casual speech people often drop です and just use a rising tone

じゃないです (ja nai desu) is the everyday polite "isn't." You may also hear ではありません (dewa arimasen) in more formal speech — same meaning, stiffer feel.

Think of です as a polite period that means "it is." Add か for a polite question mark. Swap in じゃないです to flip the meaning to "it isn't."

One line: です = is · ですか = is it? · じゃないです = isn't.

Next: Day-one greetings: おはようございます / こんにちは / こんばんは / おやすみなさい — then thanks, then a rescue set if you're lost.

See it in a sentence

1. kore wa koohii desu

   これは コーヒー です。

   This is coffee. (polite)

2. sore wa nan desu ka?

   それは なん ですか?

   What is that? (polite)

3. are wa hoteru ja nai desu

   あれは ホテル じゃないです。

   That over there isn't a hotel. (polite)

4. koko wa eki desu

   ここは えき です。

   This place is the station. (polite)

5. gakusei desu ka?

   がくせい ですか?

   Are you a student? (polite)

Watch out

です (desu) = polite "is" at the end / だ (da) = casual "is" (same job, less polite) ですか (desu ka) = polite question / rising tone alone = casual question じゃないです (ja nai desu) = polite "isn't" / じゃない (ja nai) = casual "isn't"

Try it

1. In your next story, find です (desu) or ですか (desu ka) once. Say the full line out loud and decide: statement, or question?

   Decide: statement or question.