In short

These three sentence endings colour a statement with your reaction to it. -네요 = “oh, I notice this right now” (fresh, first-hand). -군요/-는군요 = “ah, so that’s how it is” (a realization clicking into place). -지요/-죠 = ”…, right?” (something you both already assume, inviting the listener to agree). All three attach straight to the stem - no 으 buffer.

The rule

Step 1 - -네요: noticing something on the spot

Add -네요 to any stem - 동사, 형용사 or 이다 alike, with no 으: 오다 -> 오네요 (oneyo), 맛있다 -> 맛있네요 (masinneyo), 학생이다 -> 학생이네요 (haksaengineyo). It marks something you are perceiving right now, with your own senses: 비가 오네요 (biga oneyo, oh, it’s raining), 맛있네요 (masinneyo, mm, this is good). Past just stacks on -았/었-: 벌써 도착했네요 (beolsseo dochakhaenneyo, oh, you’ve already arrived). It also carries mild admiration when the fresh impression is a good one - 한국어를 잘하시네요 (Hangugeoreul jalhasineyo, you speak Korean well!). Because it reports a fresh discovery, you rarely use -네요 about your own long-known facts.

Step 2 - -군요 / -는군요: a realization sinking in

This one marks new information clicking into place (“ah, so…”), often something you were just told or worked out. The form splits by part of speech:

• 형용사, 있다/없다 and 이다 -> -군요: 예쁘다 -> 예쁘군요 (yeppeugunyo), 없다 -> 없군요 (eopgunyo), 재미있다 -> 재미있군요 (jaemiitgunyo), 학생이다 -> 학생이군요 (haksaengigunyo).
• 동사 -> -는군요: 가다 -> 가는군요 (ganeungunyo), 먹다 -> 먹는군요 (meongneungunyo).
• Past -았/었군요 for both, and the 는 drops: 갔군요 (gatgunyo, ah, so they left), 좋았군요.

The casual (반말) version is -구나 / -는구나: 맛있구나 (masitguna), 비 오는구나 (bi oneunguna).

Step 3 - -지요 / -죠: ”…, right?”

-지요 attaches straight to the stem (동사·형용사·이다), and in speech it almost always contracts to -죠: 덥다 -> 덥지요 / 덥죠 (deopjiyo / deopjo), 가다 -> 가지요 / 가죠 (gajiyo / gajo). After a vowel-final noun the copula’s 이 drops, and it drops for all three endings alike: 커피 gives 커피네요 / 커피군요 / 커피죠 (keopineyo / keopigunyo / keopijo) beside 학생이네요 / 학생이군요 / 학생이죠. It does three jobs:

• Shared assumption / statement - you present the fact as common ground: 한국은 여름이 덥지요 (Hangugeun yeoreumi deopjiyo, Korea’s summers are hot, as you know).
• Confirmation question - ”…, right?”, expecting a yes: 이거 맛있죠? (igeo masitjo?, this is delicious, isn’t it?).
• Softened suggestion / invitation with honorific -시-: 그렇게 하시죠 (geureoke hasijo, why don’t we do it that way), 가시죠 (gasijo, shall we go / after you).

One handy contrast: a plain first-time question is 뭐예요? (mwoyeyo?, what is it?), but 뭐죠? (mwojo?) muses it aloud as if you and the listener are figuring it out together - 이름이 뭐죠? (ireumi mwojo?, now, what was the name again?).

Putting them side by side

Same fact, four different attitudes: 맛있어요 (masisseoyo) is a flat it’s delicious; 맛있네요 (masinneyo) is oh, this is delicious! as you taste it; 맛있군요 (masitgunyo) is ah, so it IS delicious as the fact registers; 맛있지요? (masitjiyo?) is it’s delicious, isn’t it? fishing for your agreement. Note that two other reaction endings, -잖아요 and -거든요, wait until lesson 48.

Forms & patterns

Attachment - all three go straight onto the stem (no 으); only -군요 cares about part of speech:

Only -군요 distinguishes 동사 (-는군요) from 형용사·이다 (-군요); -네요 and -지요 never do. A ㄹ-stem drops its ㄹ before ㄴ and 는: 살다 -> 사네요 (saneyo), 사는군요 (saneungunyo) - but the ㄹ stays before ㅈ: 살지요 (saljiyo).

The three attitudes, one fact (맛있다):

Examples

Common mistakes

• 예쁘는군요. (Yeppeuneungunyo.) -> 예쁘군요. (Yeppeugunyo.) - a 형용사 takes bare -군요; only action verbs add 는.
• 가군요. (Gagunyo.) -> 가는군요. (Ganeungunyo.) - the flip side: an action verb needs -는군요, not bare -군요.
• 먹으네요. (Meogeuneyo.) -> 먹네요. (Meongneyo.) - -네요 attaches straight to the stem; there is no 으 buffer, even after a 받침.
• 갔는군요. (Ganneungunyo.) -> 갔군요. (Gatgunyo.) - after a past marker the 는 disappears; use -았/었군요 for verbs and adjectives alike.
• 이름이 뭐죠? (Ireumi mwojo?) -> 이름이 뭐예요? (Ireumi mwoyeyo?) - when you are genuinely asking for the first time, use plain 뭐예요?; -죠 adds “as we both work it out”, which is odd for a straight request.

Tips

• The evidential split. -네요 = you are perceiving it now, first-hand (you see it, taste it, hear it). -군요 = a fact clicking into place, often just-learned (“ah, so…”). -지요 = something you already assume and want confirmed. Match the ending to which of these you actually mean.
• -죠 is everywhere in speech. It is just -지요 squeezed together. Learn 그렇죠 (geureocho, right, exactly) and 맞죠? (matjo?, isn’t it?) as ready-made agreement tokens, and 가시죠 (gasijo) as a polite after you / shall we.
• Part-of-speech test for -군요. If you could put 는 in front (an action verb), say -는군요; if not (an adjective or 이다), say bare -군요. The one class it mis-sorts is 있다/없다: their modifier is the verb-style -는 (있는, 없는), but the ending they take is the adjective’s bare -군요 - 있군요, 없군요, 기다리고 있군요. -네요 and -지요 never make this distinction - they always go straight onto the stem.
• Going casual. Drop 요: -네요 -> -네 (비 오네), -군요/-는군요 -> -구나/-는구나 (맛있구나, 비 오는구나), -지요/-죠 -> -지 (그렇지, 맞지). Keep the whole utterance in one register - see 반말.