Are you learning how to express something that’s bound to happen or only natural in Korean? The grammar pattern ‘-기 마련이다’ is commonly used to talk about things that are inevitable, expected, or natural in certain situations. In this post, you’ll learn how to use ‘-기 마련이다’ with real-life examples, key usage tips, and practice exercises to help you speak more naturally in Korean.
Contents
1. Definition
‘-기 마련이다’ is used to describe a situation or behavior that is considered inevitable or a natural consequence of something. It is similar in meaning to:
- “It’s bound to…”
- “It’s only natural that…”
- “It’s inevitable that…”
2. Form (Structure)
The grammar pattern ‘-기 마련이다’ is formed by attaching ‘-기 마련이다’ to the verb stem. It is not used with adjectives. This pattern expresses that something is bound to happen or is only natural.
| Verb Type | Structure | Example |
| Present tense | verb stem + 기 마련이다 | 실수하기 마련이다 (It’s natural to make mistakes) |
| Past tense | verb stem + 았/었기 마련이었다 | 실수했기 마련이었다 (It was natural that mistakes were made) |
| Future tense | verb stem + 기 마련일 것이다 | 문제가 생기기 마련일 것이다 (A problem is bound to happen) |
| Negative form | verb stem + 지 않기 마련이다 | 생기지 않기 마련이다 (It’s rare that it doesn’t happen) |
📌Note:
- With Nouns:
When used with nouns, the structure is noun + 이기 마련이다, which means “it is natural/bound to be [noun].”
Example:- 실패는 성공의 어머니이기 마련이다.
(Failure is naturally the mother of success.)
- 실패는 성공의 어머니이기 마련이다.
- With Adjectives:
While ‘-기 마련이다’ is mainly used with verbs, in everyday Korean, it is also commonly used with some adjectives such as 어렵다 (difficult), 복잡하다 (complicated), 시끄럽다 (noisy), 피곤하다 (tired), and others.
Strictly speaking, the grammar pattern fits verbs better. However, these adjective forms are widely accepted in both spoken and written Korean, so it is perfectly fine to use them in practice exercises and daily conversation.
3. Meaning & Usage
1. To express something that is inevitable due to human nature or life
- 누구나 실수하기 마련이에요. (Everyone is bound to make mistakes.)
- 사람은 늙기 마련이에요. (People are bound to grow old.)
- 아이들은 장난치기 마련이에요. (Kids are bound to be mischievous / Kids are bound to play tricks.)
- 사랑은 변하기 마련이에요. (Love is bound to change.)
- 노력하면 결과가 있기 마련이에요. (If you make an effort, results are bound to follow.)
2. To describe a typical or common situation that happens naturally
- 초보자는 실수하기 마련이에요. (Beginners are bound to make mistakes.)
- 시험 전날에는 긴장되기 마련이에요. (It’s natural to be nervous before a test.)
- 이사하면 정신없기 마련이에요. (Moving is always hectic.)
- 날씨가 추우면 감기 걸리기 마련이에요.(You’re likely to catch a cold when it’s cold.)
- 일이 많으면 실수하기 마련이에요. (You’re bound to make mistakes when you’re too busy.)
3. Often used to give comfort or reassurance
- 처음에는 누구나 실수하기 마련이에요. (Everyone makes mistakes at first.)
- 실패도 인생의 한 부분이기 마련이에요. (Failure is a natural part of life.)
- 힘들 때도 있기 마련이에요. (There are naturally going to be hard times.)
- 마음이 약해지기 마련이에요.(It’s normal to feel weak sometimes.)
- 때로는 쉬고 싶기 마련이에요. (Sometimes, you naturally want to rest.)
4. Key Points to Remember
- Use it for general truths or common life experiences.
- It has a neutral or comforting tone.
- Do not use it for specific, one-time personal experiences.
- Commonly used with verbs describing actions or changes, not adjectives.
5. Practice Exercises
Fill in the blanks with the correct form of the verb or adjective using ‘-기 마련이다’.
- 아무리 준비해도 __________
(No matter how much you prepare, you are bound to make mistakes.) - 겨울이 되면 날씨가 __________
(When winter comes, the weather is bound to get cold.) - 처음 배우는 것은 __________
(When you learn something for the first time, it is bound to be difficult.) - 사람이 많으면 __________
(When there are many people, it is bound to be crowded.) - 아이들은 __________
(Children are bound to be noisy.) - 연습을 많이 하면__________
(If you practice a lot, you are bound to improve.) - 일이 많으면__________
(If you have a lot of work, you are bound to be tired.) - 좋은 일 뒤에는 나쁜 일도 __________
(After good things, bad things are also bound to happen.) - 모든 것은 __________
(Everything is bound to change.) - 밤에는 __________
(At night, you are bound to feel sleepy.)
6. Answers
- 실수하기 마련이다
- 추워지기 마련이다
- 어려기 마련이다
- 복잡하기 마련이다
- 시끄럽기 마련이다
- 늘기 마련이다
- 피곤하기 마련이다
- 생기기 마련이다
- 변하기 마련이다
- 졸리기 마련이다
7. Common Mistakes and Tips
⚠️ Mistake 1: Using ‘-기 마련이다’ for specific, one-time events
Incorrect: 어제 늦게 일어났기 마련이에요. ❌
(I woke up late yesterday, it was bound to happen.)
Correct: 어제 늦게 일어났어요. ✅
(I woke up late yesterday.)
💡 Tip: ‘-기 마련이다’ is used for general or repeated truths, not for single, specific events.
⚠️ Mistake 2: Mixing it with future tense markers
Incorrect: 늙을기 마련이에요. ❌
(You will be bound to age.)
Correct: 늙기 마련이에요. ✅
(It’s natural to age.)
💡 Tip: Never combine future tense endings (like -을/ㄹ) with ‘-기 마련이다’. Use only the verb stem before ‘-기 마련이다’.
⚠️ Mistake 3: Using it with imperative or request sentences
Incorrect: 조심하기 마련하세요. ❌
(Please be naturally careful.)
Correct: 조심하세요. ✅
(Please be careful.)
💡 Tip: ‘-기 마련이다’ is not used to make requests or commands.
The Korean grammar pattern ‘-기 마련이다’ is useful for expressing what is inevitable, natural, or generally true in life. It adds nuance and empathy to your sentences and helps convey deeper meaning, especially in emotional or reflective contexts. Practice using it with commonly experienced situations to internalize it more naturally.