Basic Sentence: AはBです

The “AはBです” Sentence – How to Say What Something Is (and Isn’t) in Japanese

　One of the first and most important sentence patterns you’ll learn in Japanese is:

AはBです (A wa B desu) – “A is B.”

　It’s simple, polite, and can be used for introductions, descriptions, and fun facts.　But you’ll also need to know how to say A is NOT B – that’s where じゃないです and ではありません come in instead of です.

Let’s break it down.

1. AはBです – “A is B”; "As for A, it is B."

• は (wa): a particle of topic marker. Shows what we’re talking about. Note that it's pronounced "wa", not "ha". *Particles are a type of function word that is attached to a noun and shows the relation between the noun and the predicate/verb or the rest of the sentence.

• B: what A is (BOTH A AND B should be a noun or a noun phrase).

• です (desu): polite ending that works like “is” in English.
  

Examples:

1. わたしは がくせいです。(watashi wa gakusei desu) – I am a student.

2. これは ほんです。(kore wa hon desu) – This is a book.

3. わたしのおかあさんは にほんじんです。 (watashi no okaasan wa nihonjin desu) – My mom is Japanese.
   

2. AはBじゃないです – “A is not B; As for A, it is not B” (casual polite)

• じゃないです (ja nai desu) is the most common polite negative form in conversation.

• Think of it as the friendly way to say “is not.”

• Use it when talking to friends, classmates, or in casual polite speech.

Examples:

1. わたしは せんせいじゃないです。(watashi wa sensei ja nai desu) – I’m not a teacher.

2. これは ねこじゃないです。(kore wa neko ja nai desu) – This is not a cat.

3. にほんは ヨーロッパじゃないです。(Nihon wa yooroppa nai desu) – Japan is not Europe.

💡 Note: じゃ is the contraction of では in spoken Japanese.

3. AはBではありません – “A is not B” (formal polite)

• ではありません (de wa arimasen) is the formal version of “is not.”

• Use this in speeches, news announcements, or polite business settings.

• It’s more distant and respectful.

Examples:

1. わたしは かいしゃいんではありません。(watashi wa kaishain de wa arimasen) – I am not a company employee.

2. これは わたしの かばんではありません。(kore wa watashi no kaban de wa arimasen) – This is not my bag.

3. ここは トイレではありません。(koko wa toire de wa arimasen) – This is not the restroom.
   

   

4. Fun Tip:

• In casual talk with close friends, you can even drop です entirely:

  • それは わたしじゃない。(That’s not me.)

  • But be careful – without です, it’s plain form, and might sound too direct in some situations. Japanese people are sensitive and very conscious of seniority/social hierarchy. So, you might want to go with です first.
    

5. Quick Comparison Table

Meaning	Casual Polite	Formal Polite
A is B	AはBです	AはBです
A is not B	AはBじゃないです	AはBではありません

6. Practice

✍️ Fill in the blanks with です, じゃないです, or ではありません: * Answers are below.

1. これは ペン＿＿。 (This is a pen.)

2. わたしは がくせい＿＿。 (I am not a student. casual polite)

3. ここは きょうしつ＿＿。 (This is not the classroom. formal polite)

4. わたし＿＿　アメリカじん＿＿＿。 (I am American.)

5. リンさん＿＿　カナダじん＿＿＿。（Lin is not Canadian. casual polite）
   

📃 Answers:

1. これは ペンです。

2. わたしは がくせいじゃないです。

3. ここは きょうしつではありません。

4. わたしは アメリカじんです。

5. リンさんは カナダじんじゃないです。

　How was it? Did you get all of them? This structure is the basics of forming sentences in Japanese. As you learn more vocabulary, you should be able to make more sentences on your own using this framework! Good luck on your learning journey ✈️

7. Vocabulary List (from this article)

Japanese	Reading	English Meaning
わたし	watashi	I, me
がくせい	gakusei	student
これ	kore	this
ほん	hon	book
おおさか	Oosaka	Osaka
ヨーロッパ	Yooroppa	Europe
せんせい	sensei	teacher
ねこ	neko	cat
にほん	Nihon	Japan
にほんじん	Nihonjin	Japanese person
かいしゃいん	kaishain	company employee
わたしの	watashi no	my
かばん	kaban	bag
ここ	koko	here
トイレ	toire	toilet / restroom
それ	sore	that
きょうしつ	kyoushitsu	classroom