か Particle: Asking Questions and Saying 'Or' in Japanese
Three jobs, one small particle
か does three separate things, and it's worth keeping them apart from the start. Tacked onto the end of a statement it makes a question. Wedged between two nouns it means "or." Stuck to a question word (だれ, なに, どこ) it turns that word indefinite — "someone," "something," "somewhere." No word order changes and no special verb form; か just attaches. Here are all three at work:
ヤッタンは学生ですか。
ヤッタンは がくせいですか。
Is Yattan a student?
先生はコーヒーかお茶を飲みますか。
せんせいは コーヒーか おちゃを のみますか。
Does the teacher drink coffee or tea?
Two か here: 'coffee or tea' and the final question か.
だれかいますか。
だれか いますか。
Is someone there?
At a glance, the three patterns are:
| Use | Pattern | Example |
|---|---|---|
| Question | sentence + か | これはペンですか (Is this a pen?) |
| "Or" (nouns) | A か B | コーヒーかお茶 (coffee or tea) |
| Indefinite | question word + か | だれか (someone), なにか (something) |
Turning a statement into a question
The core job: take any plain statement and add か to the end. Nothing else moves.
モチは元気ですか。
モチは げんきですか。
Is Mochi doing well?
明日、学校に行きますか。
あした、がっこうに いきますか。
Are you going to school tomorrow?
To answer, start with はい (yes) or いいえ (no):
はい、行きます。いいえ、行きません。
はい、いきます。いいえ、いきません。
Yes, I'm going. No, I'm not going.
In writing, a question ending in か usually takes a regular full stop (。) rather than a question mark, though casual writing often adds ？ too. In です/ます speech the か is expected: これはペンです on its own is a statement, so you need ですか to actually ask.
Casual questions often drop か
In casual speech, Japanese frequently leaves か off and just uses rising intonation instead. This is very common between friends:
ヤッタン、行く？
ヤッタン、いく？
Yattan, are you going?
Casual: no か, rising tone marks the question.
これ、おいしい？
これ、おいしい？
Is this tasty?
Adding か here (行くか？) can sound blunt or rough among friends, so plain rising intonation is safer in casual talk. In polite (です/ます) speech, keep the か.
AかB: offering a choice
Place か between two nouns to offer a choice between them:
ヤッタンの弟は犬か猫を飼いたいです。
ヤッタンの おとうとは いぬか ねこを かいたいです。
Yattan's brother wants to keep a dog or a cat.
月曜日か火曜日に会いましょう。
げつようびか かようびに あいましょう。
Let's meet on Monday or Tuesday.
This か connects nouns and gives a genuine either/or choice. That's the line to watch: to list nouns as examples ("things like A and B") rather than offer a choice, you'd reach for 〜や instead. Swapping one for the other changes the meaning — か is a real choice, や is a loose sampling.
Question word + か = "some-"
Attach か to a question word and it stops asking anything — it becomes vague and indefinite:
なにか食べましたか。
なにか たべましたか。
Did you eat something?
なに (what) + か = something.
どこかへ行きたいです。
どこかへ いきたいです。
I want to go somewhere.
いつかまた日本へ行きます。
いつか また にほんへ いきます。
Someday I'll go to Japan again.
The most common ones:
| Question word | + か | Meaning |
|---|---|---|
| だれ (who) | だれか | someone |
| なに (what) | なにか | something |
| どこ (where) | どこか | somewhere |
| いつ (when) | いつか | sometime / someday |
One thing learners overdo here: なにか already carries the "something," so don't force を onto it as if it were a plain object — say なにか食べる, not なにを食べるか, when you mean "eat something."
The short version
- Sentence + か = a question. Word order stays the same.
- A か B (nouns) = "A or B" — a genuine choice, unlike や.
- Question word + か = indefinite: だれか (someone), なにか (something), どこか (somewhere), いつか (sometime).
- Casual speech often drops か and uses rising intonation instead; polite です/ます speech keeps it.
Practice it
Choose the correct use of か — question, 'or', or indefinite.
＿＿＿に入れるのに最もよいものを選びなさい。
Choose the grammar pattern that best completes the sentence.
ヤッタンは学生です＿＿＿。
Frequently asked questions
How do I make a question in Japanese?
Add か to the end of a plain statement. The word order doesn't change: ヤッタンは学生です ('Yattan is a student') becomes ヤッタンは学生ですか ('Is Yattan a student?').
Can I leave off か?
In casual speech, yes — Japanese often drops か and just uses rising intonation: 行く？ ('Are you going?'). In polite です/ます speech, keep the か.
What's the difference between か and や for 'or'?
か gives a genuine choice between nouns: コーヒーかお茶 ('coffee or tea'). や instead lists examples ('things like A and B') and is not a choice.
What does だれか mean?
A question word plus か becomes indefinite. だれか = 'someone', なにか = 'something', どこか = 'somewhere', いつか = 'sometime/someday'.
Where か Particle fits
Don't confuse it with
- Conditional 〜と · N4 — The と conditional links A to an inevitable result B: 春になると、桜が咲く. Learn the plain-form formation, why B can't be a request, and how it differs from ば/たら/なら.
- で · N5 — The particle で marks where an action happens, the means or tool you use, the material, the cause, and the scope of a superlative. Learn each use and how で differs from に.
- です · N5 — です is the polite 'to be': NOUN/な-adjective + です means 'is/are.' Learn the negative じゃありません, past でした, how です attaches to い-adjectives, and the plain だ.
- が · N5 — が marks the grammatical subject and introduces new information. Learn how to use が with question words, existence (ある/いる), ability, and likes such as 好き — plus how が differs from は.
Once this clicks, go on to
- は · N5 — は marks the topic of a sentence — 'as for X.' Learn how it flags known information, its contrast use, why it's read 'wa,' and how it differs from が.
More N5 grammar to explore
Keep going with related patterns at the same level:
- まで — まで marks an end point in time or space — 5時まで ('until 5'), 駅まで ('to the station'). Learn how it pairs with から for 'from…to,' and how まで differs from までに.
- 〜ます — 〜ます is the polite verb ending. Learn ます (non-past), ません (negative), ました (past), and ませんでした (past negative), how to build the stem, and when to be polite.
- 〜ながら — 〜ながら describes doing two actions at the same time ('while doing'). Learn the formation from the ます-stem, which action is the main one, and see clear examples.
- 〜になる / 〜くなる — なる means 'become.' Learn the three patterns: noun + に + なる, な-adjective + に + なる, and い-adjective (drop い) + く + なる, plus how なる differs from する.
- 〜にする — 〜にする means to decide on or choose something (コーヒーにします = I'll have coffee) and to deliberately make X a certain way (静かにする). Learn the pattern and how it differs from なる.
- 〜のが上手 / 〜のが下手 — 上手 (good at) and 下手 (bad at) are な-adjectives. Learn NOUNが上手, VERBのが上手, the が vs を trap, and why you shouldn't call yourself 上手.