Nominalization (-기)
-기 (명사화)
Turns a verb into a noun form, commonly used in set expressions.
Pattern
Verb/Adjective stem + -기
Explanation
-기 nominalizes verbs, turning them into noun forms. It attaches directly to the verb or adjective stem: 읽다 (read) → 읽기 (reading), 쓰다 (write) → 쓰기 (writing), 듣다 (listen) → 듣기 (listening). This is commonly seen in TOPIK test section names: 읽기 (reading), 듣기 (listening), 쓰기 (writing).
-기 is used in many important grammatical patterns: -기 전에 (before doing), -기 시작하다 (start doing), -기 쉽다/어렵다 (easy/hard to do), -기 때문에 (because of doing), -기(를) 바라다 (hope to). These set expressions are essential for intermediate Korean.
Compared to -(으)ㅁ, the other nominalization ending, -기 is generally used for subjective, future-oriented, or ongoing situations. -(으)ㅁ tends to be more formal, objective, and factual. Understanding when to use each is a key skill for TOPIK Level 3.
Examples
한국어 읽기가 점점 쉬워져요.
Hangugeo ilkgiga jeomjeom swiwojyeoyo.
Korean reading is gradually getting easier.
운동하기 시작했어요.
Undonghagi sijakhaesseoyo.
I started exercising.
이 문제는 풀기 어려워요.
I munjeneun pulgi eoryeowoyo.
This problem is hard to solve.
건강하기를 바랍니다.
Geonganghagireul baramnida.
I hope you stay healthy.
Common Mistakes
Wrong
한국어 읽는 것가 쉬워져요.
Correct
한국어 읽기가 쉬워져요.
With adjectives like 쉽다/어렵다 describing difficulty, use -기, not -는 것.
Wrong
운동하기를 시작했어요.
Correct
운동하기 시작했어요.
With 시작하다, 끝나다, etc., 를 after -기 is usually omitted.
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