Grammar › Particles › か
か — questions & "or"
The marker of the unknown. At the end of a sentence it makes a question; between two things it means "or".
The short version
Add か to the end of a sentence and it becomes a question — no word order changes, no rising intonation needed. Placed between choices, AかB means "A or B", and かどうか means "whether or not". One idea underneath both: something is unknown.
学生ですか。 — are you a student? (question)
コーヒーかお茶 — coffee or tea (choice)
The question marker
In polite speech, か is how you ask. The statement stays exactly as it is; か at the end does the work a question mark and rising tone do in English.
元気ですか？
How are you? / Are you well? (か = question)
何をしますか。
What will you do? (question word 何 + か)
"Or" — and "whether or not"
Between two options, か marks them as alternatives: 本か雑誌 ("a book or a magazine"). Tack かどうか onto a clause to fold in the "…or not" and embed the question inside a bigger sentence.
言えるかどうか。
Whether or not (you) can say it. (かどうか = whether or not)
Watch out
🗣 Casual questions drop か. Among friends, か mostly disappears and a rising intonation carries the question instead — 「どこ行く？↗」 for 「どこへ行きますか」. Keep か for polite speech and writing.
9月かな、どこ行く？
September maybe — where are we going? (casual question, no か)
か + question word = "some-". Attach か to a question word and it turns indefinite: 誰 "who" → 誰か "someone"; 何 "what" → 何か "something"; どこ "where" → どこか "somewhere".
Next: は vs が → · と / や — and → · All grammar
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