Tensification
The plain consonants ㄱ, ㄷ, ㅂ, ㅅ, ㅈ become the tense sounds ㄲ, ㄸ, ㅃ, ㅆ, ㅉ after certain batchim. That is why 학교 (school) is pronounced [학꾜].
받침 [ㄱ/ㄷ/ㅂ] + ㄱ/ㄷ/ㅂ/ㅅ/ㅈ → 된소리 ㄲ/ㄸ/ㅃ/ㅆ/ㅉ
How It Works
A plain consonant tenses up after a [k], [t], or [p] batchim sound. The spelling never changes — only the sound hardens. It is easy for learners to miss, yet essential to sounding natural.
Transformation Examples
See — and hear — how the spelling turns into its actual pronunciation.
학교
[학꾜]
hakkyo
school
국밥
[국빱]
gukppap
rice soup
식당
[식땅]
sikttang
restaurant
읽다
[익따]
iktta
to read
Exceptions & Notes
Tensification has many conditions and exceptions. It also occurs after the ㄹ of Sino-Korean words (발달 → [발딸]) and after the modifier ending -ㄹ (갈 곳 → [갈꼳]). Listening often is faster than memorizing every rule.
Check Your Understanding
How is 식당 (restaurant) pronounced?
Which sound is NOT produced by tensification?