Understanding Korean vowels is fundamental to mastering verb conjugation and pronunciation. Korean vowels are classified into three categories based on their sound quality, and this classification affects how verbs are conjugated.

Korean Vowel Classification

Korean has 10 basic vowels:

ㅏ ㅑ ㅓ ㅕ ㅗ ㅛ ㅜ ㅠ ㅡ ㅣ

These vowels are grouped into three categories:

Bright Vowels (양성모음)

ㅏ ㅑ ㅗ ㅛ

  • When pronounced, these vowels sound brighter and more open
  • Many words with bright meaning use these vowels
  • Example: 행복하다 (to be happy)

Dim Vowels (음성모음)

ㅓ ㅕ ㅜ ㅠ

  • When pronounced, these vowels sound dimmer and more closed
  • Many words with darker or heavier meaning use these vowels
  • Example: 우울하다 (to be depressed)

Neutral Vowels (중성모음)

ㅡ ㅣ

  • These vowels are neutral and can combine with either bright or dim vowels

Connecting Vowels (매개모음)

Connecting vowels are used when conjugating verbs to create:

  • Past tense
  • Polite form (~요)

The two connecting vowels are:

Connecting Vowel Used With
아 Bright vowels (ㅏ, ㅑ, ㅗ, ㅛ)
어 Dim vowels (ㅓ, ㅕ, ㅜ, ㅠ) and neutral vowels (ㅡ, ㅣ)

Why This Matters

Think of it this way: bright vowels pair with the bright connecting vowel (아), and dim vowels pair with the dim connecting vowel (어). This creates a harmonious sound flow in Korean speech.

Practical Application

Here’s how vowel classification affects common verbs:

Bright Verbs (use 아):

  • 하다 (do) - ends with ㅏ
  • 보다 (see) - ends with ㅗ
  • 가다 (go) - ends with ㅏ
  • 오다 (come) - ends with ㅗ
  • 받다 (receive) - ends with ㅏ
  • 알다 (know) - ends with ㅏ

Dim Verbs (use 어):

  • 주다 (give) - ends with ㅜ
  • 묻다 (ask) - ends with ㅜ
  • 걷다 (walk) - ends with ㅓ
  • 두다 (put) - ends with ㅜ

Neutral Verbs (use 어):

  • 있다 (exist/be) - ends with ㅣ

Summary

Understanding vowel harmony in Korean helps you:

  1. Conjugate verbs correctly
  2. Pronounce words naturally
  3. Recognize patterns in vocabulary

Remember: Bright vowels attract bright connecting vowels (아), and dim vowels attract dim connecting vowels (어).