동사 활용: -아요 / -어요

목표 (Mục Tiêu / Learning Objectives)

After this lesson, you will:

Understand how Korean verbs conjugate in casual polite (아요/어요) form
Apply the vowel harmony rule to choose between -아요 and -어요
Conjugate common verbs correctly

Tiếng Việt So Sánh (Vietnamese Comparison)

Vietnamese: Verbs don't change

Tôi đi. (I go.)
Cô ấy đi. (She goes.)
Verb "đi" is the same for all subjects.

Korean: Verbs must change

나는 가요. (I go.)
학생은 가요. (A student goes.)
The verb 가다 becomes 가요 in casual polite form.

This is fundamental to Korean grammar. Every verb must be conjugated.

Khái Niệm (The Concept)

Korean verbs conjugate to show:

Tense (past, present, future)
Politeness level (formal, polite, casual)
Mood (statement, question, command)

In this lesson, we focus on the present tense, casual polite (아요/어요) form, which is the most common in everyday speech and exam contexts.

Vowel Harmony Rule (Quy Tắc Hòa Hợp Nguyên Âm)

Rule 1: Verbs with ㅏ or ㅗ vowel → add -아요

가다 (ga-da) → 가요 (ga-yo)
  └─ ㅏ in the stem
  
하다 (ha-da) → 해요 (hae-yo)
  └─ Special case: ㅏ + ㅏ becomes ㅐ
  
오다 (o-da) → 와요 (wa-yo)
  └─ Special case: ㅗ gets special treatment

Rule 2: Verbs with other vowels → add -어요

먹다 (meog-da) → 먹어요 (meog-eo-yo)
  └─ ㅓ in the stem

읽다 (ilg-da) → 읽어요 (ilg-eo-yo)
  └─ ㅓ in the stem

마시다 (ma-si-da) → 마셔요 (ma-shyeo-yo)
  └─ ㅣ in the stem

규칙 (The Pattern)

Basic Conjugation

Dictionary Form (사전형): 동사 -다
                           verb -da
                           
Remove 다 → get the stem
             
Stem + ㅏ/ㅗ vowel → Stem + -아요
Stem + Other vowel → Stem + -어요

Special Cases

하다 (do): 해요 (not 하아요)
오다 (come): 와요 (special irregular)
보다 (see): 봐요 (special: ㅗ → ㅘ)

예제 (Examples)

Example 1: ㅏ vowel → -아요

가다 (go)
├─ 가 + 다
├─ Remove 다
├─ 가 (stem with ㅏ)
└─ 가 + -아요 = 가요

합니다 → 해요 (special case for 하다)

Example 2: ㅓ vowel → -어요

먹다 (eat)
├─ 먹 + 다
├─ Remove 다
├─ 먹 (stem with ㅓ)
└─ 먹 + -어요 = 먹어요

읽다 (read)
├─ 읽 + 다
├─ Remove 다
├─ 읽 (stem with ㅓ)
└─ 읽 + -어요 = 읽어요

Example 3: ㅣ vowel → -어요

마시다 (drink)
├─ 마시 + 다
├─ Remove 다
├─ 마시 (stem with ㅣ)
└─ 마시 + -어요 = 마셔요 (with contraction)

흔한 실수 (Common Errors)

❌ Mistake 1: Using same ending for all verbs

WRONG: 먹아요, 마시아요, 가어요 (mixing up the rules)
CORRECT: 먹어요, 마셔요, 가요

❌ Mistake 2: Forgetting conjugation

WRONG: 나는 먹다. (informal, dictionary form in speech)
CORRECT: 나는 먹어요. (polite, for conversation)

❌ Mistake 3: Not recognizing special cases

WRONG: 나는 하아요. (should be 해요)
CORRECT: 나는 해요. (do)

어휘 (Vocabulary)

Infinitive	-아요/-어요	English	Vowel
가다	가요	go	ㅏ
하다	해요	do	special
오다	와요	come	special
먹다	먹어요	eat	ㅓ
마시다	마셔요	drink	ㅣ
읽다	읽어요	read	ㅓ
있다	있어요	have/exist	ㅣ
없다	없어요	not have	ㅓ

퀴즈 (Quiz)

Flashcard (1/5)

-아요

Conjugate 읽다 (read) in -어요 form:

읽아요읽어요읽습니다

요약 (Summary)

Korean verbs conjugate based on vowel harmony:

ㅏ/ㅗ vowels → add -아요
Other vowels → add -어요
Special cases (하다, 오다, 보다) have irregular forms

Mastering this rule is essential because every Korean verb you use must be conjugated correctly.

Next lesson: We'll apply this conjugation to the five most common verbs.