How to Identify Korean Verb and Adjective Stems Easily – A Guide for Beginners

Table of Contents & Structure

- Introduction

- What Is a Stem?

- How to Identify Verb and Adjective Stems

- What Is an Ending?

- Basic Rule: Stem + Ending

- Practice Quiz: Identify the Stem and Ending

- Tips for Mastery

- Wrap-Up & Next Steps

- Appendix: Answer Key & Explanations – Stem & Ending Quiz

Introduction

Many Korean learners wonder why it's so important to distinguish between the stem and the ending of a verb or adjective.

Understanding this distinction makes conjugating verbs and adjectives much easier and dramatically improves your ability to form natural sentences and carry on conversations more fluently.

Learners who’ve mastered the difference between stems and endings often report noticeable improvements in their grammar skills—and others around them notice it too!

 

What Is a Stem?

In Korean grammar, the stem is the core part of a verb or adjective to which endings are attached. It carries the primary meaning of the word and does not change regardless of tense, politeness level, or grammatical structure—only the ending changes.

Stems are essential because they form the foundation of conjugation. Once you know the stem of a verb or adjective, you can apply various endings to express time (past, present, future), formality (formal, polite, casual), mood (declarative, interrogative, imperative), and more.

 

How to Identify Verb and Adjective Stems

While learning the base form of Korean verbs and adjectives is the easiest and most reliable way to identify their stems, it’s not the only path.

In Korean, the dictionary form of verbs (ending in “-다”) is rarely used as-is in everyday sentences. Instead, verbs are typically combined with various endings that express tense, politeness level, sentence type, and more. The verb stem is simply the portion of the base form that comes before “-다.” For example, in “가다” (to go), “가-” is the stem.

Adjectives follow the same pattern. Their base form also ends in “-다”—as in “예쁘다” (to be pretty), “작다” (to be small), or “맛있다” (to be delicious). Removing “-다” reveals the stem: “예쁘-,” “작-,” and “맛있-,” respectively. So, identifying adjective stems works the same way as with verbs.

Although verbs and adjectives differ in grammatical usage and meaning, the method for extracting the stem from the dictionary form remains consistent. In short, knowing the base form allows you to easily locate the stem, whether it’s a verb or an adjective.

That said, it’s entirely possible—and beneficial—to practice identifying stems by observing how words appear in real sentences. For instance, from “가요” you can infer that “가-” is the stem, or from “예쁩니다,” you can identify “예쁘-” as the stem. Developing this skill in context enhances understanding and fluency.

In conclusion, while starting with the base form is a solid foundation, it’s not the only way to grasp stems. Training with various conjugated forms is also practical. Many Korean textbooks and learning resources emphasize both the base and conjugated forms, encouraging learners to practice finding stems within real sentences.

 

What Is an Ending?

In Korean grammar, an ending is a grammatical element attached to the stem of a verb or adjective. These endings are essential because they indicate tense, politeness level, sentence type (declarative, interrogative, imperative, or propositive), and how clauses are connected. Endings transform a simple verb or adjective stem into a complete, meaningful expression that fits within a sentence.

Korean endings are classified into various types, such as final endings, pre-final endings, connective endings, and more. Each type serves a specific role in constructing grammatically correct and contextually appropriate sentences.

For a detailed breakdown of each ending type and practical usage examples, please refer to the post below.

🔖 What is “어미” in Korean? Easy Grammar for Understanding Korean Sentence Structure

Basic Rule: Stem + Ending

The core structure of Korean predicates (verbs and adjectives) is based on a simple but powerful rule: Stem + Ending. This rule applies whether you're forming polite statements, asking questions, giving commands, or connecting clauses. The stem is the part of the word that carries the lexical meaning, while the ending conveys grammatical information like tense, mood, speech level, or connection.

However, when combining stems and endings, specific phonological or morphological changes may occur. These changes include vowel contractions, consonant assimilation, irregular conjugations, and even spelling shifts, depending on the stem's final character and the ending used.

 

📌 Visual Examples (Verbs):

- 가 + -요 → 가요 ("to go") – Regular

- 먹 + -습니다 → 먹습니다 ("to eat") – Regular

- 걷 + -어요 → 걸어요 ("to walk") – Irregular “ㄷ” → “ㄹ” change

- 듣 + -어요 → 들어요 ("to listen") – Irregular “ㄷ” → “ㄹ” change

- 만들 + -어요 → 만들어요 ("to make") – Regular, ends with “ㄹ”

 

📌 Visual Examples (Adjectives):

- 예쁘 + -어요 → 예뻐요 ("to be pretty") – Vowel contraction (“ㅡ” + 어 → 어)

- 작 + -아요 → 작아요 ("to be small") – Regular

- 낫 + -아요 → 나아요 ("to recover") – Irregular “ㅅ” is dropped

- 길 + -어요 → 길어요 ("to be long") – Regular

- 시끄럽 + -어요 → 시끄러워요 ("to be noisy") – Irregular “ㅂ” → 우/오 change

 

🔍 Types of Changes to Watch For:

- Vowel contraction: Happens when vowel endings like -아/어요 merge with the stem vowel.

• Example: 예쁘 + 어요 → 예뻐요.

 

- Consonant assimilation: Some consonants change to ease pronunciation.

• Example: 듣 + 어요 becomes 들어요.

 

- Irregular conjugations: Certain verbs and adjectives don't follow regular conjugation rules. Common irregular types include:

• ㄷ-irregular (e.g., 듣다 → 들어요)

• ㅅ-irregular (e.g., 낫다 → 나아요)

• ㅂ-irregular (e.g., 덥다 → 더워요)

• 르-irregular (e.g., 모르다 → 몰라요)

 

These changes are essential for natural and grammatically correct Korean and are covered in more detail in the following sections.

 

👉 For more profound insight into conjugation rules, irregular types, and more examples, continue reading the detailed breakdowns in the next blog posts.

 

Common Stem & Ending Pairs for Practice

One of the most effective ways to master Korean verb and adjective conjugation is through hands-on practice with real examples. By analyzing and identifying the stem and ending in various word forms, learners can gain a deeper understanding of how Korean sentences are constructed.

To support this, we recommend using an interactive chart or list that presents standard stem and ending pairs. This tool should include both regular and irregular verbs and adjectives in different tenses and politeness levels. Seeing the components side by side allows learners to spot recurring patterns and phonological changes more easily.

 

For instance, the word 갔어요 ("went") can be broken into:

- Stem: 가- (from the verb 가다, "to go")

- Ending: -았어요 (past tense + polite ending)

 

Encourage learners to go through similar words and actively try to:

- Identify the base form (dictionary form)

- Separate the stem from the ending

- Note any sound or spelling changes that occurred during conjugation

 

This type of practice not only reinforces grammar knowledge but also builds intuition for how Korean verbs and adjectives behave in real sentences.

 

👉 A list of suggested Stem + Ending examples and practice charts will follow in the next section for guided learning.

 

Practice Quiz: Identify the Stem and Ending

In the sentences below, the underlined verbs or adjectives are conjugated forms. Try to split each into its stem and ending. Pay attention to irregular conjugation or phonological changes.

 

Instructions

① Read each sentence.

② Identify and underline the conjugated verb/adjective.

③ Write down the stem and the ending.

④ Mark any irregular or phonological changes you notice.

 

Sentences for Practice

1. 저는 요리를 잘 해요.

2. 어제 친구를 만났어요.

3. 날씨가 정말 좋아요.

4. 오늘도 회사에 가요.

5. 아침에 늦게 일어났어요.

6. 방이 너무 깨끗해요.

7. 그 사람이 예뻐요.

8. 우리는 맛있게 먹었습니다.

9. 지금 달리고 있어요.

10. 숙제를 다 했어요.

11. 여름은 정말 더워요.

12. 그 배우는 목소리가 낮아요.

13. 나는 할머니를 자주 찾아뵈어요.

14. 아이가 밖에서 놀고 있어요.

15. 문제를 아주 쉽게 풀었어요.

16. 우리는 어제 잤어요.

17. 이 음식은 너무 매워요.

18. 그 친구는 성격이 착해요.

19. 아버지는 지금 회사에 계세요.

20. 저녁을 준비했어요.

21. 이 책은 내용이 어려워요.

22. 저는 매일 피아노를 연습해요.

 

👉 See: [Appendix: Answer Key & Explanations – Stem & Ending Quiz]

 

Tips for Mastery

To confidently navigate Korean stem and ending variations, especially when dealing with irregular forms, here are some key strategies:

 

How to Spot Irregular Stems and Endings

- Learn the most common irregular patterns:

• ㅂ irregular: The final ㅂ in the stem changes to 우 or 오 before a vowel (e.g., 춥다 → 추워요, 맵다 → 매워요).

• ㄷ irregular: The final ㄷ in the stem changes to ㄹ before a vowel (e.g., 걷다 → 걸어요).

• 르 irregular: 르 often causes a doubling of the ㄹ and adds an extra syllable (e.g., 모르다 → 몰라요, 빠르다 → 빨라요).

• ㅅ irregular: The final ㅅ may disappear before a vowel (e.g., 짓다 → 지어요, 낫다 → 나아요).

• ㅎ irregular: The ㅎ may drop or combine with an ending (e.g., 좋다 → 좋아요 is regular, but 하얗다 → 하얘요 is irregular).

• 하 irregular: 하다 often contracts with endings (e.g., 하다 → 해요, 했습니다).

 

- Watch for vowel harmony or contraction rules (e.g., 예쁘다 → 예뻐요, not 예쁘어요).

 

- Listen to native speech and observe where stem shifts happen—this helps reinforce rules in context.

 

Memorization and Pattern Recognition Strategies

- Group by type: Learn regular vs. irregular verbs/adjectives separately. Group similar irregulars to reduce confusion.

 

- Create mini flashcards: Write stem + ending combinations for verbs and adjectives you frequently encounter.

 

- Use visual aids: Charts and color-coded stem/ending pairs help make patterns stand out.

 

- Practice with transformation drills: Take a dictionary form and write out all major conjugations.

 

- Immerse and notice: Read and listen to real-life Korean content and try to “spot the stem and ending” in action.

 

- Quiz yourself: Use apps or paper-based self-quizzes that require splitting words into stem and ending.

 

With enough exposure and pattern tracking, even irregulars will begin to feel predictable.

 

Wrap-Up & Next Steps

You’ve just taken a deep dive into one of the most fundamental building blocks of Korean grammar: the relationship between stems and endings. By learning how to identify verb and adjective stems and understanding how they combine with various endings, including irregular forms, you now have a strong foundation for parsing and constructing Korean sentences with greater confidence.

 

Let’s review what you’ve learned:

- The stem is the part of a verb or adjective that carries the core meaning.

- The ending provides additional grammatical information such as tense, politeness, or mood.

- Most Korean verbs and adjectives follow regular stem-ending patterns, but common irregulars like ㅂ, ㄷ, ㅅ, 르, and 하 should be memorized.

- Recognizing patterns and practicing with real examples helps you internalize these structures quickly.

 

What’s next?

In the upcoming post, I’ll explore 어말어미 (Final Endings) in depth—these are the sentence-final endings that give Korean its unique rhythm, tone, and expressiveness. You’ll learn how final endings work in both formal and casual speech, how they vary across moods (declarative, interrogative, imperative, etc.), and how they signal relationships between speakers.

Stay tuned—mastering 어말어미 will unlock your ability to express nuance and speak naturally in Korean!

 

Appendix: Answer Key & Explanations – Stem & Ending Quiz

1. 저는 요리를 잘 해요.

- Stem: 하- / Ending: -어요

- "하다" becomes "해요" due to contraction (irregular: 하 → 해)

 

2. 어제 친구를 만났어요.

- Stem: 만나- / Ending: -았어요

- Regular past tense form: 만나 + -았어요 → 만났어요

 

3. 날씨가 정말 좋아요.

- Stem: 좋- / Ending: -아요

- "좋다" uses the ㅗ vowel, so it takes -아요 → 좋아요

 

4. 오늘도 회사에 가요.

- Stem: 가- / Ending: -요

- 가다 is an exception that keeps its stem: 가 + -요 → 가요

 

5. 아침에 늦게 일어났어요.

- Stem: 일어나- / Ending: -았어요

- Regular: 일어나다 (to get up) → 일어나 + 았어요 → 일어났어요

 

6. 방이 너무 깨끗해요.

- Stem: 깨끗하- / Ending: -어요

- Adjective ending in 하다 contracts: 깨끗하 + -어요 → 깨끗해요

 

7. 그 사람이 예뻐요.

- Stem: 예쁘- / Ending: -어요

- “ㅡ” - deletion rule: 예쁘 + -어요 → 예뻐요

 

8. 우리는 맛있게 먹었습니다.

- Stem: 먹- / Ending: -었습니다

- Formal past tense: 먹 + 었습니다 → 먹었습니다

 

9. 지금 달리고 있어요.

- Stem: 달리- / Ending: -고

- Connective ending: 달리 + 고

 

- Stem: 있- / Ending: -어요

- Sentence ending: 있 + -어요

 

10. 숙제를 다 했어요.

- Stem: 하- / Ending: -었어요

- 하다 becomes 하 + 었었요 → 했어요 (irregular contraction, past tense)

 

11. 여름은 정말 더워요.

- Stem: 덥- / Ending: -어요

- “ㅂ” - irregular: 덥다 → 더 + 워요 → 더워요

 

12. 그 배우는 목소리가 낮아요.

- Stem: 낮- / Ending: -아요

- Regular: 낮 + -아요 → 낮아요

 

13. 나는 할머니를 자주 찾아뵈어요.

- Stem: 찾아뵈- / Ending: -어요

- Honorific verb: 찾아뵈다 → 찾아뵈 + -어요 → 찾아뵈어요

 

14. 아이가 밖에서 놀고 있어요.

- Stem: 놀- / Ending: -고

- Connective ending: 놀- + -고

 

- Stem: 있- / Ending: -어요

- Sentence Ending: 있- + -어요

 

15. 문제를 아주 쉽게 풀었어요.

- Stem: 풀- / Ending: -었어요

- Regular past: 풀다 → 풀 + 었어요 → 풀었어요

 

16. 우리는 어제 잤어요.

- Stem: 자- / Ending: -았어요

- 자다 (to sleep) + 았어요 → 잤어요

 

17. 이 음식은 너무 매워요.

- Stem: 맵- / Ending: -어요

- “ㅂ”-irregular: 맵다 → 매우 + 어요 → 매워요

 

18. 그 친구는 성격이 착해요.

- Stem: 착하- / Ending: -어요

- 하다-based adjective contraction: 착하 + -어요 → 착해요

 

19. 아버지는 지금 회사에 계세요.

- Stem: 계시- / Ending: -어요

- Honorific verb: 계시다 → 계시 + 어요 → 계세요

 

20. 저녁을 준비했어요.

- Stem: 준비하- / Ending: -었어요

- 하다-conjugation: 준비하 + 었어요 → 준비했어요 (irregular contraction)

 

21. 이 책은 내용이 어려워요.

- Stem: 어렵- / Ending: -어요

- “ㅂ”-irregular: 어렵다 → 어려 + 워요 → 어려워요

 

22. 저는 매일 피아노를 연습해요.

- Stem: 연습하- / Ending: -어요

- 하다 contraction: 연습하 + 어요 → 연습해요