Writing Balance Rule: Write a square box that is slightly wider at the top and narrows slightly toward the bottom. The final closing stroke seals the bottom cleanly.
1. Meaning
mouth
classifier for things with mouths (people, domestic animals, wells, cannons, etc.)classifier for bites or mouthfulsopening or entrance (e.g., cave entrance, bottle mouth)
noun / measure wordNeutral#anatomy#measure words#containers and openings
Sample Usage
他张开嘴。
tā zhāng kāi zuǐ.
He opened his mouth.
我家有五口人。
wǒ jiā yǒu wǔ kǒu rén.
There are five people in my family.
2. Sound
/[kʰoʊ̯²¹⁴]/Tone: 214
口
kǒukou3
|
++
ˇ(214)
=kǒu
Initial Consonant
k
Type: Aspirated Velar
Sounds like: k sound as in 'key' or 'cat'
Aspirated
Airflow Tactile Test: Strong gust of air from throat! Tissue held in front MUST fly forward.
Tongue & Mouth Position: Back of the tongue raises to make contact with the soft palate, then releases with a strong burst of air.
Final Rhyme
ou
Vowel Group: -o vowel group
Sounds like: -ou rhymes with 'oh' or 'soul'
Mouth Shape Guide: Pronounce as standalone vowel 'oh'.
Common Learner Trap: Keep vowel quality steady across all 4 tone contours.
Tone
T3 (214)
2 → 1 → 4 (214)
3rd Tone (Low-Dipping)
Tone Pitch & Cadence: Tone 3 dips low in pitch and rises back up, similar to how an English speaker says 'Really?' in disbelief.
Sandhi: When followed by another 3rd tone character, kǒu changes to a 2nd tone (35) through tone sandhi (e.g., kǒuwèi becomes kóuwèi).
👂
Listening trap: Beginners often mistake the dipping Tone 3 for a flat tone when spoken quickly in normal conversation.
👋
Physical Tone Gesture: Trace a checkmark in the air: dip down from your starting pitch to your lowest register, then glide upward with energy.
3. Writing
Topology: Single character · Strokes: 3 strokes
Writing Balance Rule: Write a square box that is slightly wider at the top and narrows slightly toward the bottom. The final closing stroke seals the bottom cleanly.
4. Components
Radical口 · Mouth Radical (mouth, opening, speech)
Semantic Clue (形旁):口 (Depicts an open human mouth or an opening/cave.)
A single standalone box representing the human oral cavity, drawn as three continuous strokes: a vertical left wall, a top-right bent stroke, and a bottom sealing stroke.
丨 Left vertical stroke
𠃍 Top and right turning stroke
一 Bottom horizontal closing stroke
Phonetic Family (形声字家族)
7· Phonetic Root: 口 (kǒu)
5. History
Liushu category: Pictogram (象形)
Origin: In Oracle Bone script, 口 was drawn as an oval or square outline representing human lips parted to speak or eat.
Semantic Evolution: Originally representing a physical mouth, its meaning expanded naturally to represent any mouth-like opening, and later became a standard counting unit for family members and mouths to feed.
It is one of the most foundational Kangxi radicals (Radical 30), appearing in hundreds of characters related to eating, speaking, and shouting.
6. Sinosphere
🇻🇳
Sino-Vietnamese
khẩu
The Chinese 3rd tone corresponds closely to the Vietnamese hỏi tone (hỏi/ngã).
🇯🇵
Kanji (Japanese)
On: コウ (kō) / ク (ku) / Kun: くち (kuchi)
🇰🇷
Hanja (Korean)
구 (gu)
Sound Shift Bridge: The ancient initial velar stop /k/ and open vowel rhyme match closely across neighboring East Asian cognates and Indo-European structural borrowings.
7. Memory
Vivid Mnemonic Story
Picture an open square cave representing a giant mouth shouting out loud into the valley.
Phonetic Family (形声字家族)
日
rìsunA mouth 口 with a horizontal dividing line inside becomes the sun 日.
中
zhōngmiddleA mouth 口 pierced right down the middle with a vertical line becomes 'middle' 中.
回
huíto returnA smaller mouth inside a larger mouth represents turning around or returning 回.
Lookalikes & Traps (形近字)
日(rì)
口 is completely empty inside; 日 has a horizontal line slicing across the middle.
中(zhōng)
口 is an open box; 中 has a vertical line passing straight through it.
8. Mastery
Active Recall Challenge
我家有五[___]人。
Clue: kǒu
Common Learner Pitfall
Confusing 口 with 日 due to their similar box-like shapes.
Memory Prompts
Recognition: When you see the box shape 口 representing an opening, what is its pinyin and primary meaning?
Production: How do you write the character for 'mouth' and what is its standard measure word usage?
Real-World Video Context
Watch authentic native speakers pronounce and explain this word in real-world YouTube videos.
Search theme
Accent preference
Results are live YouTube search — accents and levels aren't verified.
口kǒumouth
Speed:
Searching YouTube for native pronunciation videos...