The Same Vowel-Selection Principle
The basic choice between -았어요 and -었어요 uses the same last-vowel judgment learned for -아요 and -어요 .
In the regular consonant-final examples in this lesson, ㅏ or ㅗ leads to -았어요 , while other last vowels lead to -었어요 .
Vowel contraction, ㅡ deletion, and the 하다 pattern are covered in the next lesson.
Vowels ㅏ and ㅗ: -았어요
In the regular consonant-final examples taught here, choose -았어요 when the stem's last vowel is ㅏ or ㅗ.
Examples
Dictionary Form · Stem + Suffix · Past Tense
잡다 · 잡- + -았어요 · 잡았어요
작다 · 작- + -았어요 · 작았어요
Other Vowels: -었어요
In the regular consonant-final examples taught here, choose -었어요 when the stem's last vowel is not ㅏ or ㅗ.
Examples
Dictionary Form · Stem + Suffix · Past Tense
먹다 · 먹- + -었어요 · 먹었어요
읽다 · 읽- + -었어요 · 읽었어요
Vowel-final stems and ㅡ-final stems may undergo contraction or deletion, which is covered in the next lesson.
Common Mistake: Double Conjugation
A common beginner mistake is adding the past tense marker to a word that is already conjugated in the present tense.
Attach -았/었- directly to the basic stem, not to the -아/어- form.
Wrong: 먹어었어요
Correct: 먹었어요 ( 먹 + 었어요 )