Korean Probably Grammar: Patterns, Rules and Examples

What Is Korean Probably Grammar?

Korean probably grammar is the group of endings that tell the listener "I am not certain". Korean has no single word for "probably". The speaker chooses an ending that shows where the guess comes from: what the speaker sees, what the speaker works out, or what the speaker expects to happen. Choosing the right ending is the main skill of this section.

The table lists six everyday meanings and the pattern that carries each one. Use it as a quick chooser, then open the lesson.

Romanization: naeireun biga ol geot gatayo; biga oneun geot gatayo; oneul gibuni joa boyeoyo; biga ona bwayo; biga ol tende usaneul gajyeogaseyo; naeireun nuni oljido mollayo. The shapes -(으)ㄹ, -(으)ㄴ and -는 before the helper word change the time of the guess, and the helper word stays the same. The next section gives the order in which to learn the patterns.

Which Pattern Should You Learn First?

Learn the three A2 patterns first, then the six B1 patterns, then the four B2 patterns. The order follows how often you meet each pattern in daily Korean and how much each one depends on the one before.

Begin with -(으)ㄹ 것 같다, because it talks about the future and takes only one extra sound rule. Add -(으)ㄴ/는 것 같다 next, because it covers the present and the past. Then learn -아/어 보이다 for appearances. Only after these three do the B1 patterns make sense, because most of them are stronger or more specific versions of the same idea. A typical study time is one sitting of about 15 minutes per lesson, plus practice. The next section summarises every pattern.

The Patterns, Grouped by Meaning

Each pattern below has a short summary, one example with audio and a link to the full lesson. The patterns are grouped by level, and within each level by how close the meaning is to everyday speech.

Beginner Patterns (A2)

These three patterns cover most daily guesses: the future, the present and past, and appearance.

-(으)ㄹ 것 같다

The lesson on -(으)ㄹ 것 같다 teaches the guess about a future event or a state you have not seen yet. It attaches -(으)ㄹ to a stem and adds 것 같다; a present or past impression uses -(으)ㄴ/는 것 같다 instead. Example: 내일은 비가 올 것 같아요. (naeireun biga ol geot gatayo.) = "I think it will rain tomorrow."

-(으)ㄴ/는 것 같다

The lesson on -(으)ㄴ/는 것 같다 covers a guess about a present or past state from what you see or hear. It has four shapes, one each for verb present, verb past, adjective present and noun, and it also softens an opinion. Example: 비가 오는 것 같아요. (biga oneun geot gatayo.) = "I think it is raining."

-아/어 보이다

The lesson on -아/어 보이다 teaches the pattern for how something looks. It takes the 아/어 form of an adjective and adds 보이다, and it does not work with action verbs. Example: 오늘 기분이 좋아 보여요. (oneul gibuni joa boyeoyo.) = "You look happy today."

Intermediate Patterns (B1)

These six patterns add stronger or more specific meanings: signs seen in other people, a likely situation with a concern, a possibility, a denial or a confident guess.

-나 보다

The lesson on -나 보다 teaches a guess from signs, for verbs and for 있다/없다. The speaker thinks aloud about what is going on, usually about someone or something else. Example: 비가 오나 봐요. (biga ona bwayo.) = "It seems it is raining."

-(으)ㄴ가 보다

The lesson on -(으)ㄴ가 보다 is the twin of -나 보다 for adjectives and nouns. It also infers a state from evidence the speaker can see or hear. Example: 친구가 아픈가 봐요. (chinguga apeunga bwayo.) = "My friend seems to be sick."

-(으)ㄹ 텐데

The lesson on -(으)ㄹ 텐데 states a probability and then adds a concern, a request or a contrast in the next clause. Example: 비가 올 텐데 우산을 가져가세요. (biga ol tende usaneul gajyeogaseyo.) = "It will probably rain, so take an umbrella."

-(으)ㄹ지도 모르다

The lesson on -(으)ㄹ지도 모르다 states a possibility with less certainty than -(으)ㄹ 것 같다. The speaker says "it could happen", not "it will". Example: 내일은 눈이 올지도 몰라요. (naeireun nuni oljido mollayo.) = "It might snow tomorrow."

-(으)ㄹ 리가 없다

The lesson on -(으)ㄹ 리가 없다 strongly denies a possibility, based on the speaker's reasoning and not on something seen. Example: 그 사람이 거짓말을 할 리가 없어요. (geu sarami geojinmareul hal riga eopseoyo.) = "There is no way he would lie."

-(으)ㄹ걸요

The lesson on -(으)ㄹ걸요 gives a casual guess, and speakers often use it to disagree gently with what the listener expects. It is spoken Korean only. Example: 그 사람은 벌써 갔을걸요. (geu sarameun beolsseo gasseulgeollyo.) = "He has probably gone already."

Advanced Patterns (B2)

Each line gives the pattern's key phrase, a link to its lesson and one example.

-(으)ㄴ/는 모양이다 (it appears that). Example: 비가 오는 모양이에요. (biga oneun moyangieyo.) = "It appears that it is raining."

-(으)ㄹ 듯하다 (it seems that, formal). Example: 내일은 비가 올 듯합니다. (naeireun biga ol deutamnida.) = "It seems it will rain tomorrow."

-지 싶다 (I suspect that). Example: 아마 벌써 집에 갔지 싶어요. (ama beolsseo jibe gatji sipeoyo.) = "I suspect he has gone home already."

-나 싶다 (I wonder if). Example: 무슨 일이 있나 싶었어요. (museun iri inna sipeosseoyo.) = "I wondered if something was wrong."

With every pattern mapped, the next section shows how to pick between the ones that look alike.

How Do You Choose between Look-Alike Patterns?

Choose by asking three questions: When is the guess about, what is the evidence, and how sure is the speaker? The answers separate most look-alike pairs. The table gives the main pairs and the one-line rule for each.

For example, 그 사람은 벌써 갔을걸요 (geu sarameun beolsseo gasseulgeollyo) sounds like a confident correction: "He has probably gone already, you'll find." The sentence 그 사람은 벌써 간 것 같아요 (geu sarameun beolsseo gan geot gatayo) sounds like a gentle opinion. Both are guesses, but only the first pushes back. The full comparison pages are collected in Confusing Grammar Compared. Next comes practice.

Where Can You Practise?

Practise by reading one pattern at a time, then testing yourself, then reviewing. The site's tools cover each step.

• Read and listen: open any lesson above and press the audio buttons to hear each example.
• Check yourself: the Korean beginner grammar test mixes A1 and A2 items with feedback after each answer, including the A2 guess patterns.
• Review: the beginner Korean grammar flashcards include short grammar notes with audio.
• Related lessons: future guess -겠- and future tense -(으)ㄹ 거예요 cover the future forms that sit next to -(으)ㄹ 것 같다.

Level plans are on the Beginner Grammar and Intermediate Grammar pages. The last section lists what this hub does not cover.

What Does This Section Not Cover?

This hub covers the sentence endings that express a guess, a likelihood or an impression, which is the core of Korean probably grammar. It does not cover other parts of the grammar, and each has its own hub. The list gives the closest neighbours.

• Case and topic markers: Korean Particles.
• Past, present and future forms: Korean Tenses.
• Saying "not": Korean Negation.
• Casual, polite, formal and honorific styles: Korean Speech Levels.
• Forms that describe nouns: Korean Modifiers.
• Helper verbs such as 보다 and 있다: Auxiliary Verb Constructions.
• Endings that join clauses: Korean Connectors.

For the wider map of the grammar, return to Korean Sentence Endings or to the main Korean Grammar hub.

Frequently Asked Questions

What is the difference between -(으)ㄹ 것 같다 and -(으)ㄴ/는 것 같다?

The first guesses about the future or about something you have not seen yet: 내일은 비가 올 것 같아요. The second infers a present or past state from what you see or hear: 비가 오는 것 같아요. The shape of the modifier (-(으)ㄹ versus -(으)ㄴ/는) carries the time, and 것 같다 stays the same.

Can I use these patterns for my own feelings?

Mostly yes with -(으)ㄴ/는 것 같다, as in 피곤한 것 같아요 ("I think I'm tired"), which also softens opinions. Patterns such as -나 보다 and -(으)ㄴ가 보다 infer something from signs, so they suit other people. Saying 제가 피곤한가 봐요 sounds like you are observing yourself from outside.

Are these patterns tested on the TOPIK?

Guess patterns appear across the TOPIK I and TOPIK II grammar range, and the A2 patterns are common in reading and listening items. The levels shown on this page are editorial estimates and should be checked against official materials. Learn the A2 patterns first, because they carry the most daily conversation.

Which pattern sounds most formal?

-(으)ㄹ 듯하다 belongs to a written or formal style, as in 내일은 비가 올 듯합니다. The common patterns also have formal forms ending in -ㅂ니다, such as 올 것 같습니다. -(으)ㄹ걸요 is spoken Korean only, and -나 싶다 and -지 싶다 usually sound like thinking aloud.

Where are the comparison pages for look-alike patterns?

Comparison pages sit in the Confusing Grammar Compared section. This hub links to -(으)ㄹ 것 같다 vs -나 보다 and -(으)ㄹ 텐데 vs -(으)ㄹ 것 같다. Each page gives a short rule and the same example sentence with each pattern.