の: Possessive 's, the 'One' Pronoun, and Nominalizer (N5)
What it means
The particle の connects two nouns, with the owner or describer coming first: A の B means "A's B" or "B of A." From that one idea grow three more uses — の replacing a repeated noun, の making a verb act like a noun, and の as a soft spoken-question ending. They look identical, so context tells them apart.
これはヤッタンの本です。
これは ヤッタンの ほんです。
This is Yattan's book.
モチは日本語の先生です。
モチは にほんごの せんせいです。
Mochi is a Japanese(-language) teacher.
日本語の先生 = teacher of Japanese; the first noun describes the second.
走るのが速いですね。
はしるのが はやいですね。
You're fast at running, aren't you.
走るの turns the verb 走る into a noun: 'the act of running.'
How to form it
| Use | Pattern | Example |
|---|---|---|
| Possessive / linking | Noun + の + Noun | ヤッタンの本 (Yattan's book) |
| "One" (replacing a noun) | Adjective/Noun + の | 赤いの (the red one) |
| Nominalizer | Verb (plain) + の | 食べるの (eating / to eat) |
| Casual question | Sentence (plain) + の？ | どうしたの？ (What's wrong?) |
Linking two nouns: A's B
This is の's home base. The first noun owns or defines the second:
これはヤッタンの弟のかばんです。
これは ヤッタンの おとうとの かばんです。
This is Yattan's little brother's bag.
Two の's chain here because there are genuinely three nouns.
先生の車は青いです。
せんせいの くるまは あおいです。
The teacher's car is blue.
Replacing a noun: "the red one"
When the noun is obvious, drop it and let の stand in for it — like English "one":
赤いのをください。
あかいのを ください。
The red one, please.
赤いの = 赤い + (noun) → 'the red one.'
モチは大きいのがほしいです。
モチは おおきいのが ほしいです。
Mochi wants the big one.
Nominalizer: turning a verb into a noun
Add の to a plain-form verb to treat the whole action as a noun. The action can then be a subject (〜のが) or topic (〜のは):
ヤッタンは走るのが速いです。
ヤッタンは はしるのが はやいです。
Yattan is fast at running.
モチはケーキを食べるのが好きです。
モチは ケーキを たべるのが すきです。
Mochi likes eating cake.
食べるの = 'eating'; のが好き expresses liking an activity.
日本語を話すのは楽しいです。
にほんごを はなすのは たのしいです。
Speaking Japanese is fun.
Casual question: の？
In speech, ending a plain sentence with の (rising tone) makes a gentle, often caring question. It's common with friends and family:
どうしたの？
どうしたの？
What's wrong?
Softer and warmer than どうしましたか.
ヤッタン、今日は学校に行かないの？
ヤッタン、きょうは がっこうに いかないの？
Yattan, aren't you going to school today?
Common mistakes
- Chaining の where you don't need it. Use a fresh の only for each real noun link. "Japanese teacher" is 日本語の先生 (one link), not 日本語のの先生.
- Dropping the noun when it isn't clear. 赤いの works only if everyone knows what "thing" is meant. Out of the blue, keep the noun: 赤い車 ("a red car").
- Forgetting the verb must be plain form before の. It's 食べるのが好き, never 食べますの. Nominalizing の attaches to the dictionary/plain form.
- Reversing the order. A の B means B belongs to A. ヤッタンの先生 = "Yattan's teacher," while 先生のヤッタン = "Yattan, who belongs to the teacher" — a very different meaning.
Quick recap
- AのB links two nouns: "A's B" / "B of A" (ヤッタンの本).
- の can replace a known noun: 赤いの = "the red one."
- Plain verb + の makes the action a noun: 走るのが速い, 食べるのが好き.
- Casual spoken question: plain sentence + の？ (どうしたの？).
Your turn
Choose the correct use of の: possessive, 'one,' nominalizer, or question.
Start the 5-question drill →Frequently asked questions
How is の used to show possession?
Put the owner first and の second: ヤッタンの本 means 'Yattan's book.' The pattern is A の B = 'A's B' or 'B of A.' It also links a describing noun to another, like 日本語の先生 ('Japanese teacher').
What does 赤いの mean without a noun after it?
の stands in for an understood noun, like English 'one': 赤いの = 'the red one,' 大きいの = 'the big one.' Use it only when the listener already knows what thing you mean.
How does の turn a verb into a noun?
Add の to a plain-form verb to treat the action as a noun, then mark it with が or は: 走るのが速い ('running is fast'), 食べるのが好き ('likes eating'), 話すのは楽しい ('speaking is fun').
Why do people end questions with の?
In casual speech, a plain sentence plus の (rising tone) makes a soft, friendly question, often showing concern: どうしたの? ('What's wrong?'). It's warmer than the formal 〜か.