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Grammar Intermediate TOPIK II · Level 3–4 Intermediate Korean 1 · Unit 6

-나 보다

-나 보다: I Guess — Evidence-Based Guess with Verbs

Guess or vague recognition from evidence — typically after verbs (-나 보다).

Before this, make sure you know: -아요 / -어요 , -았-/-었- , -어 보다

How to form it

When Form Example
Verb stem -나 보다 가나 보다 / 오나 보다 / 하나 보다
After -었- -었나 보다 갔나 보다 / 비가 왔나 보다
Polite -나 봐요 가나 봐요 / 자나 봐요

-나 보다 is the everyday I guess / it seems that sits on evidence — wet streets, a dark window, a friend who isn’t answering. Gloss: mainly the verb side of the guess pair taught with -는가 보다 / -(으)ㄴ가 보다.

우리말샘 does not always list the whole idiom as one headword; it describes -나 in guess constructions (-나 하다 / -나 싶다 / -나 보다) and 보다 as an auxiliary adjective in -은가/는가/나 보다. Classroom Korean still teaches -나 봐요 as a chunk.

Shape

밖에 비가 오나 봐요.
동생이 자나 봐요.
이미 갔나 봐요.
요즘 요가를 하나 봐요.
문을 안 닫았나 봐요.

Clues matter. You are not announcing certainty; you are reading signs.

불이 꺼져 있네. 벌써 잤나 봐.
신발이 없네. 나갔나 봐요.

Hobby talk:

사진 찍으러 자주 가나 봐요.
주말마다 등산하나 봐요.

Three different 보다 traps

FormJob
-나 보다guess from evidence
보다comparison than
-어 보다try doing
-을까 보다its own modality pair
커피보다 차를 마셔요.     comparison
커피 마셔 봐요.           try it
커피 마시나 봐요.         I guess they drink coffee

English reuses look / see / than / try. Korean splits them. Mixing the four is the fastest way to sound fluent and wrong.

Pair with -는가 보다

-는가 보다 / -(으)ㄴ가 보다 is the same guess family, different attachment spelling. Courses print both so input does not panic you.

가나 봐요. / 가는가 봐요.     both: guessing about going

Do not invent a meaning split like “-나 보다 = sure.” The split is mostly form.

Learner traps

  1. Comparison 보다 after a noun mistaken for this chunk.
  2. -어 보다 try mistaken for a guess.
  3. Forcing -나 보다 onto every adjective when -은가 보다 is what you heard.

Ask: am I inferring from clues, usually about an action? If yes, -나 보다. If you are comparing two nouns, you want 보다, not this page.

Do not confuse it with

-는가 보다 / -(으)ㄴ가 보다

it seems that / I guess / judging by appearances... (inferential deduction from signs)

-어 보다

try doing — and in the past, "have you ever"

-을까 보다

thinking I might — a plan you are still weighing

보다

than — the comparison particle

Taught alongside this

On the jabi learning path, this appears in 오랜만에 영화를 보니 정말 재미있었어요 (It was really fun to see a movie after a long time.) — Intermediate Korean 1, Unit 6, on the theme of hobby. These come with it:

-는가 보다 the same guess, attached differently -으니 on doing it, I found that — discovery rather than cause -은 결과 as a result of — the written summary phrase

Words used above

Tap the speaker to hear it read aloud by your browser.

-나 보다-na bodaI guess… (from evidence)
가나 봐요gana bayoI guess they’re going
추측chucheukguess / conjecture
증거jeunggeoevidence
취미chwimihobby

Quick check

No sign-up, no score saved — just see if it stuck.

1. 비가 왔나 봐요 means…

2. Which is NOT this -나 보다?

3. Best sister form for many adjective guesses?

Common questions

Is this the same as -을 것 같다?

Same neighbourhood (guessing), different shape and feel. Learn -나 보다 as the ‘seems, from what I can tell’ routine.

Can I use it on adjectives?

You will hear related -은가 보다 forms. This page’s printed pattern is the -나 보다 verb side; see neunga-boda for the paired attachment.

What about 봐 as ‘try’?

eo-boda is -어 보다 ‘give it a try.’ Different construction.

Is -을까 보다 related?

eulkka-boda is another 보다 family member with its own job — do not merge them.