Please choose either coffee or tea.
Will you come tomorrow?
Lists alternatives, often in the pattern AかBか. Also used in embedded questions meaning 'whether or not'.
Which would you like, coffee or tea?
I don't know whether he will come or not.
Attaches to interrogative words (何, 誰, どこ, etc.) to form indefinite pronouns like 何か (something), 誰か (someone).
See also: 何か
Someone knocked on the door.
Is there something to eat?
Expresses doubt, uncertainty, or rhetorical questioning, often in casual speech. Can follow other particles like のか, かな.
Is that really so? (expressing doubt)
Huh, can that really happen?
Emphatic prefix attached to adjectives, e.g., か弱い (very weak). Limited to a few fixed expressions; not freely productive.
See also: か弱い
She asked for help in a very weak voice.
-al, -ial, -ic, -ical, -ish, -y (adjective-forming suffix)
Archaic suffix that forms adjectives or adverbs from indeclinable words, e.g., 定か (certain). Not productive in modern Japanese; found in set words.
See also: 定か
His whereabouts are not certain.
Archaic adverbial usage, equivalent to あのように or そのように. Not used in modern conversation.
In classical Japanese, か can be used to mean 'in that way'.
I haven't decided yet whether I'll go or not.
Is it really okay, I wonder?
かどうか is the fixed phrase for 'whether or not', while か alone can also simply list alternatives (AかBか) or mark a direct question.
かな softens the doubt or wondering expressed by か, giving a more casual, musing tone than か by itself.
か is the plain, casual question marker, while ですか is its polite equivalent used in formal or polite speech.
か is the neutral, standard question particle usable in any register, while かい is a softer, more familiar variant typically used by men or in casual speech.
か is a shorter, more casual particle for listing alternatives, while または is more formal and clearly separates distinct options.
か attached to a question word expresses simple uncertainty (何か, いつか), while やら (何やら, いつやら) adds a vaguer, more musing tone.
か is the plain, direct question marker, whereas こと used as a question (its gentle interrogative sense) sounds softer and more reflective.
か is the plain, neutral question marker, whereas かしら adds a musing, uncertain tone typically linked to women's speech.
Kana-only particle; no kanji form exists.
The particle か is native Japanese, with a long history as a question marker and alternative-listing particle. Its use as an indefinite marker (after interrogatives) and as an emphatic prefix developed from earlier interrogative and exclamatory functions. The archaic suffix and adverb uses are remnants of older grammatical patterns.
か is the plain question particle for direct questions, while かね softens the question into a reflective, doubtful musing.