1. Basic structure
| Part of speech | Formation with どの | Example structures | Notes |
|---|
| Interrogative determiner | どの + N | どの本／どの人／どの部屋 | “Which” must be followed by a noun |
| Quantity/degree | どのくらい／どのぐらい + V/A | どのくらい時間がかかりますか | “About how long/how much” (≈ どれくらい) |
| Area | どの辺（へん） | 駅はどの辺ですか | “Which area/around where” (friendly) |
| Polite for referring to people | どの方（かた） | 先生はどの方ですか | More polite than どの人 |
2. Main meanings & detailed analysis
- “どの + N” asks to identify a specific noun among many choices: “Which …?”.
- “どのくらい/どのぐらい” asks about degree, time, quantity: “how much/how long”.
- It cannot stand alone; if there is no noun, use どれ (which one).
- For origin/affiliation, どこのN is usually more natural: どこの国／どこの会社.
3. Example sentences
- どの本が一番おもしろいですか。
Which book is the most interesting? - どの部屋ですか。
Which room is it? - どのシャツが田中さんのですか。
Which shirt is Mr. Tanaka's? - 先生はどの方ですか。
Which person is the teacher? - 駅はどの辺ですか。
Whereabouts is the station? - ここからどのくらいかかりますか。
About how long does it take from here? - 日本語のクラスはどの曜日がありますか。
On which days is the Japanese class held? - どの国の料理が好きですか。
Which country's cuisine do you like?
4. Usage & nuances
- Always put a noun after どの; if not, switch to どれ.
- To ask about a person politely: use どの方 instead of どの人.
- To ask degree: どのくらい/どのぐらい goes with V/A/名詞+です.
- For origin/affiliation, どこのN is very natural in conversation: どこの会社ですか.
5. Comparison, distinctions, and similar patterns
| Pattern | Meaning | Difference | Short example |
|---|
| どの + N | Which (modifies a noun) | Must have N | どの映画が好き？ |
| どれ | Which one | Stands alone | どれがあなたのですか。 |
| どちら | Which one (polite)/where | Usually two choices; polite | AとB、どちら？ |
| どこの + N | Which N from where | Asks origin/affiliation | どこの会社ですか。 |
| どのくらい | About how much | Degree/Duration | どのくらい時間が必要？ |
6. Additional notes
- “どのくらい” ≈ “どれくらい” (both are common; どれくらい is slightly more colloquial).
- For specific time points, use “何時／何分／何日” instead of どの.
- “どの辺” is casual; use “どのあたりですか” for a more polite tone.
7. Variations & fixed expressions
- どの方 (polite way to ask about a person)
- どのくらい／どのぐらい (how much/how long)
- どの辺（へん）／どのあたり (which area/whereabouts)
- どのNでも (any N ...)
8. Common mistakes & JLPT traps
- Using どの by itself: × どのが好き？ → ✓ どれが好き？ or ✓ どの映画が好き？
- Confusing どの with どこの when asking origin: ✓ どこの国／会社.
- Forgetting the noun after どの, leading to insufficient information in JLPT answers.
- Mixing up どのくらい (degree) with いくつ/いくら (quantity/price). Choose according to the question's meaning.
