Key Facts
- Hangul: 잘하다 (jalhada)
- Meaning: to be good at; to do well
- Level: A1
- Part of speech: verb
- Stem: 잘하
- Conjugation class: 하다 type
- Grammar: The skill takes 을/를 (한국어를 잘하다), and the person who is skilled takes 은/는 or 이/가.
- Honorific polite: 잘하세요
- Usage: Very frequent compliment: 잘하시네요 (you are good at it). Written as one word for both 'be good at' and 'do well'; learners often add a space (잘 해요).
What Does 잘하다 Mean?
- to be good at: Used for skill, e.g. 요리를 잘하다 (to be good at cooking).
- to do well: Used for doing something properly or well, e.g. 발표를 잘하다 (to do well on a presentation).
잘하다 is to be good at something and to do it well. The skill takes 을/를, as in 한국어를 잘하다, being good at Korean, and 요리를 잘하다, being good at cooking. The person with the skill takes 은/는 or 이/가. A one-off result uses the same verb: 발표를 잘했어요 means the presentation went well.
It is written as one word in both senses: 한국어를 잘해요 (good at Korean) and 발표를 잘했어요 (did well). Learners often add a space after 잘, but the dictionary verb is the joined 잘하다. The compliment 잘하시네요 uses the honorific stem.
Which Set Phrases Use 잘하다?
- 잘하시네요: You are good at it; an honorific compliment.
- 한국어를 잘하다: To be good at Korean.
- 발표를 잘하다: To do well on a presentation.
How Do You Pronounce 잘하다?
잘하다 is read as spelled, with a light h in the middle. The past 잘했어요 is [잘해써요] and the formal 잘합니다 is [잘함니다]. The future 잘할 거예요 is [잘할꺼예요].
How Do You Use 잘하다 in a Sentence?
동생은 노래를 잘해요.
My younger sibling is good at singing.
동생은 (my younger sibling) is the topic and 노래를 is the thing done well. The skill word 노래 takes 를.
어제 발표를 잘했어요.
I did well on the presentation yesterday.
어제 (yesterday) and 발표를 (the presentation) set a single event. The past 잘했어요 reports that it went well.
한국어를 잘하고 싶어요.
I want to be good at Korean.
한국어를 is the skill. The want form 잘하고 싶어요 says the speaker wants to become good at Korean.
How Does Jalhada Conjugation Work?
잘하다 is a 하다 verb. 하 + 여 becomes 해, so the polite present is 잘해요 and the past is 잘했어요. Consonant endings keep 하: 잘하면, 잘합니다.
잘하다
| Form | Korean | Romanization | Rule |
|---|---|---|---|
| Polite present | 잘해요 | ||
| Polite past | 잘했어요 | ||
| Polite future (plan) | 잘할 거예요 | ||
| Polite future (intention or guess) | 잘하겠어요 | ||
| Formal present | 잘합니다 | ||
| Formal past | 잘했습니다 | ||
| Formal future | 잘할 것입니다 | ||
| Casual present | 잘해 | ||
| Casual past | 잘했어 | ||
| Casual future | 잘할 거야 | ||
| Want to (polite) | 잘하고 싶어요 | ||
| Honorific polite | 잘하세요 | ||
| Because / and then | 잘해서 | ||
| If (conditional) | 잘하면 | ||
| Present modifier (before a noun) | 잘하는 | ||
| Past modifier (before a noun) | 잘한 | ||
| Future modifier (before a noun) | 잘할 | ||
| Negative (long form) | 잘하지 않아요 |
The short negative 안 잘해요 is not used. Say 잘 못해요 for 'not good at it' or 잘하지 않아요, and 잘 안 해요 means you rarely do it, so it is a different statement.
Sound Changes
| Form | Korean | Sounds like |
|---|---|---|
| Polite past | 잘했어요 | [잘해써요] |
| Polite future | 잘할 거예요 | [잘할꺼예요] |
| Polite future guess | 잘하겠어요 | [잘하게써요] |
| Formal present | 잘합니다 | [잘함니다] |
| Formal past | 잘했습니다 | [잘핻씀니다] |
| Formal future | 잘할 것입니다 | [잘할꺼심니다] |
| Casual past | 잘했어 | [잘해써] |
| Casual future | 잘할 거야 | [잘할꺼야] |
| Long negative | 잘하지 않아요 | [잘하지 아나요] |
Common Mistake with 잘하다
Wrong: ✗ 한국어가 잘해요.
Correct: ✓ 한국어를 잘해요.
Why: 잘하다 is transitive, so the skill takes 을/를, not 이/가.
What Is Easy to Confuse with 잘하다?
| Word | How to tell it from 잘하다 |
|---|---|
| 못하다 | 못하다 is the opposite: to be poor at or unable to do something. |
| 잘 하다 | Written with a space, 잘 하다 is the adverb 잘 plus 하다. For 'be good at' and 'do well', the standard spelling is the joined 잘하다. |
A Compliment after a Presentation
Two coworkers are talking the day after a presentation. Jisu praises a completed result, Alex expresses a learning goal, and Jisu adds a comment about Alex's skill.
Jisu
어제 발표를 정말 잘했어요.
Eoje balpyoreul jeongmal jalhaesseoyo.
You did really well on your presentation yesterday.
Alex
고마워요. 한국어를 더 잘하고 싶어요.
Gomawoyo. Hangugeoreul deo jalhago sipeoyo.
Thank you. I want to get better at Korean.
Jisu
설명도 잘해요.
Seolmyeongdo jalhaeyo.
You explain things well too.
The first line leaves out “you” because the speakers know whose presentation they mean. 어제 발표를 잘했어요 can therefore report your own success or praise someone else's, depending on the conversation. Korean does not mark the subject's person in 잘했어요.
The final 설명도 잘해요 adds explaining as another skill. 도 means “also”. Naming the activity distinguishes clear explanations from confident delivery or accurate Korean.
What Else Can 잘하다 Praise?
| Phrase | Meaning | What is being praised |
|---|---|---|
| 요리를 잘하다 | to be good at cooking | Ability in preparing food. |
| 노래를 잘하다 | to sing well | Singing skill rather than enjoyment of singing. |
| 말을 잘하다 | to speak well | Effective speaking in the situation. |
| 잘했어요 | well done / you did well | A completed action or a good choice. |
말을 잘하다 can praise clear explanations or persuasive speech. It does not always mean knowing many languages. 한국어를 잘하다 names one language specifically; 말을 잘하다 evaluates speaking more broadly. Listen for the object before assuming which ability is being praised.
잘했어요 can also approve a decision. If a friend finally took a needed rest, the reply may mean “you did the right thing”. It need not praise technical skill. The past ending fits a choice already made, just as it fits a presentation already delivered.
Where Will You Hear 잘하다?
Language exchanges, music lessons and sports practice give you plenty of occasions for 잘하다. A teacher may praise a particular attempt with 잘했어요; someone hearing you play for the first time may comment on your skill with 잘해요. The past form focuses on the result, while the present can describe ability.
잘하시네요 adds respect toward the person whose skill you notice. It is a useful compliment to an unfamiliar adult. 잘했어 is casual and can sound warm between friends, but it may feel overly familiar if said to a senior colleague. Choose the relationship as carefully as the tense.
잘하다 and 좋아하다 answer different questions. Being good at singing does not establish that you enjoy it, and liking Korean does not establish fluency. Use the two words separately when explaining both your interests and your abilities.
How Do Spacing and Negation Change the Message?
For the senses on this page, write 잘하다, 잘해요 and 잘했어요 as single words. When 잘 modifies a different verb, it stays separate: 잘 먹다 means “eat well”. Recognising the actual verb helps you avoid applying the joined spelling to every phrase beginning with 잘.
잘 못해요 expresses difficulty doing something well. 잘 안 해요 usually says you do not do it often or tend not to do it. A person who rarely cooks might still be an excellent cook; frequency and ability are different facts. The lesson on negating 하다 verbs explains the broader pattern.
The modifier 잘하는 describes someone with a skill, while 잘한 can refer to something done well. In the table, both come from the same stem 잘하. The first suits ongoing ability; the second looks back at a completed performance or choice.
Words for Talking about Progress
| Korean | Meaning | Useful distinction |
|---|---|---|
| 연습 | practice | Work done to improve a skill. |
| 실력 | ability / skill level | The ability that 잘하다 evaluates. |
| 발표 | presentation | A specific performance you can praise afterward. |
| 노래 | song / singing | An activity someone may do well. |
Use the hobbies vocabulary lesson to find more activities you can pair with 잘하다, from music to games and sport.
Mini Drill: Praise the Right Thing
- Complete “good at Korean”: 한국어____ 잘해요.
- Give the polite past of 잘하다.
- Give the present modifier: 잘하다 → ____.
- Choose “rarely do it”: 잘 못해요 or 잘 안 해요?
Show drill answers
- 한국어를 잘해요.
- 잘했어요.
- 잘하는.
- 잘 안 해요. 잘 못해요 concerns ability or difficulty.
Quick Self-Test
- Does 노래를 잘하다 mean liking singing?
- Can 잘했어요 praise a good decision?
- Does 잘해요 itself tell you whether “I” or “you” is the subject?
Show answers
- No. It describes singing skill.
- Yes. Context supplies what was done well.
- No. The conversation or an explicit subject supplies that information.
Frequently Asked Questions
What Is the Polite Present of 잘하다?
잘해요.
How Do I Compliment Someone's Skill?
Say 잘하시네요.
What Is the Opposite of 잘하다?
못하다, meaning to be poor at or unable to do something.
What Is the Difference between 잘하다 and 잘 하다?
In standard spelling, 잘하다 is one word both for being skilled and for doing something well on one occasion, as in 발표를 잘했어요. Learners often write 잘 해요 with a space; for these meanings, join it: 잘해요.
Which Words Are Related to 잘하다?
What Should You Learn Next?
Learn 못하다 as the opposite, then 좋아하다 and 공부하다. Add 연습하다 to talk about how you practise a skill. For the rule behind these forms, read how 하다 words become 해요, then try another stem in the Korean verb conjugator or browse the Korean verb dictionary.