Core Pattern Rule: Expressing Surprise with -다니 / -라니
This pattern is used to express surprise, disbelief, or a strong emotional reaction to a fact you've just learned. It's equivalent to saying "To think that...!" or "I can't believe...!" in English. It often forms a complete exclamatory sentence on its own.
Formation
The ending changes based on the word type.
Verbs & Adjectives: Attach -다니 directly to the stem.
가다 → 가다니 (To think that you're going!)
예쁘다 → 예쁘다니 (To think that it's pretty!)
합격하다 → 합격하다니 (To think that you passed!)
Nouns: Attach -(이)라니.
Nouns ending in a consonant + -이라니
월요일 → 월요일이라니 (To think it's Monday!)
품절 → 품절이라니 (To think it's sold out!)
Nouns ending in a vowel + -라니
공짜 → 공짜라니 (To think it's free!)
거짓말 → 거짓말이라니 (To think it's a lie!)
벌써 월요일이라니! / 네가 합격하다니! / 이렇게 맛있는 게 공짜라니! / 내 생일을 까먹다니!
Nuance: Positive vs. Negative Surprise
The emotion conveyed by -다니 / -라니 depends entirely on the context and your tone of voice. It can express everything from delight to frustration.
Positive Surprise & Admiration
Use it to react to good news, amazing facts, or something pleasantly unexpected.
Context: Someone passed a difficult exam, or you received a wonderful gift.
Example: 네가 합격하다니! (To think that you passed! That's amazing!)
Negative Surprise & Disbelief
Use it to react to bad news, frustrating situations, or something you find hard to accept.
Context: You have to work overtime again, or you just found out the exam is tomorrow.
Example: 또 야근이라니! (I can't believe I have to work overtime again!)
Neutral Shock
Sometimes it's just pure shock without a strong positive or negative feeling.