Several parts combine into one character.

問 is a beautifully transparent compound: 門 (gate) cradling 口 (mouth). The picture is unmistakable — a visitor stands at the threshold and opens his mouth: "to ask, to inquire after someone." Ancient Chinese etiquette literally pictured: you arrived at the gate of a friend's home and called out an inquiry about their well-being.

More elegantly, 問 forms a perfect minimal pair with 聞 (to hear / listen): same gate, different sense organ inside. 門 + 口 (mouth) = ask. 門 + 耳 (ear) = listen. The two characters embody the conversation itself — speaking and hearing, framed by the same threshold.

Korean reading "mun." Saturates the vocabulary of inquiry: 質問 (jilmun, question), 問題 (munje, problem / question), 疑問 (uimun, doubt / query), 訪問 (bangmun, visit), 問答 (mundap, Q&A), 學問 (hakmun, scholarship — literally "learning by asking"). 學問 deserves attention — the noun for "scholarship" is "study + ask," reflecting the Confucian view that real learning happens through questioning.

Mandarin wèn, 4th tone (simplified 问). 问题 (wèntí, problem) is one of the highest-frequency nouns in conversational Chinese. 请问 (qǐngwèn, "may I ask") is the polite opening for any question to a stranger — every Chinese learner masters this in week one. 访问 (fǎngwèn, to visit) preserves the original "go to the gate and inquire" sense.

Japanese on-reading モン (mon) — 質問 (shitsumon), 疑問 (gimon, doubt), 問題 (mondai, problem), 学問 (gakumon, scholarship). Kun-readings: とう (tou, to ask) — 安否を問う, "to inquire after someone's safety" — and とい (toi, the noun "question").

Memory aid: gate (門) + mouth (口) — calling a question through the gate. Pair with 聞 (gate + ear = listening).