目錄
Open a calendar or the notes app on a phone, and you may sometimes see Koreans write things like 「공부하기」 or 「사진 정리하기」 on their to-do lists. If you look closely, these expressions do not seem like complete sentences you would normally hear in conversation, and they are missing some of the familiar sentence endings. In fact, this 「-기」 attached to the end of a verb plays a very important role in everyday Korean. Put simply, it works like a kind of magic clip that can take actions such as “eat,” “go,” “study,” or “organize” and turn them directly into noun-like units, making them into things like “the act of eating” or “the act of going.”
Why Does 「-기」 Appear So Often in Calendars? The Core of Concise Korean Notes and Lists
Verbs are very important in Korean, but notes, headings, and lists usually do not require complete sentences. In these situations, 「-기」 can turn a verb into a nominalized item, much like writing “confirm reservation” or “organize photos” on a Chinese to-do list. It does not necessarily need a subject, nor does it always need a fully expressed tense. The main point is to turn an action into something that can be listed as an item.
Basic Usage and Attachment Rules for 「-기」
Attachment Rules
| What It Attaches To | Form | Examples |
| Verb | Verb stem＋기 | 가기、먹기、공부하기 |
| Adjective | Adjective stem＋기 | 쉽기、어렵기 |
| 하다 verb | Noun＋하기 | 예약하기、정리하기 |
| Negation | 안＋verb＋기 | 안 늦기 |
「-기」attaches directly to the stem and does not change according to whether the stem ends in a final consonant. 하다 verbs become 「하기」; for example, 「공부하다」 becomes 「공부하기」. In a sentence, 「-기」 can function as a subject or object, and it can also appear in list items and headings.
Usage ① of 「-기」｜Turning a Verb into a Noun
This is the most basic nominalization function. After adding 「-기」 to a verb, the resulting form can take particles such as 「가」「를」「는」 like a noun and can also be incorporated into a larger sentence.
- Example: 한국어를 배우기는 재미있어요.
Romanization: han-gu-geo-reul bae-u-gi-neun jae-mi-i-sseo-yo
Translation: Learning Korean is fun.
「배우기」turns “to learn” into something that can be described. - Example: 아침에 일찍 일어나기가 어려워요.
Romanization: a-chi-me il-jjik i-reo-na-gi-ga eo-ryeo-wo-yo
Translation: Getting up early in the morning is difficult.
「일어나기」functions as the subject and is followed by an adjective. - Example: 혼자 여행하기를 좋아해요.
Romanization: hon-ja yeo-haeng-ha-gi-reul jo-a-hae-yo
Translation: I like traveling alone.
「여행하기」becomes the object of what the speaker likes.
Usage ② of 「-기」｜Using It in To-Do Lists and Calendars
「-기」is very common in to-do lists, phone notes, study plans, and calendars. In this use, it is not a complete sentence but rather a shorthand list item. It reads like something that needs to be done.
- Example: 오전 10시 회의 준비하기
Romanization: o-jeon yeol-si hoe-ui jun-bi-ha-gi
Translation: Prepare for the meeting at 10 a.m.
This is a calendar-style expression and does not require a complete sentence ending. - Example: 여행 전에 숙소 예약 확인하기
Romanization: yeo-haeng jeo-ne suk-so ye-yak hwa-gin-ha-gi
Translation: Confirm the accommodation reservation before the trip.
「확인하기」turns the action into a to-do item. - Example: 오늘 할 일: 사진 정리하기, 세탁하기
Romanization: o-neul hal il sa-jin jeong-ni-ha-gi se-tak-ha-gi
Translation: Today’s tasks: organize photos, do the laundry.
Multiple actions in a list can all use 「-기」.
Usage ③ of 「-기」｜Using It in Titles and Instructional Text
Korean textbooks, video titles, notices, and app buttons also frequently use 「-기」. It keeps headings short and action-oriented, which makes it more suitable for information interfaces than a complete sentence.
- Example: 비행기표 싸게 사기
Romanization: bi-haeng-gi-pyo ssa-ge sa-gi
Translation: Buying plane tickets cheaply.
This concise form is common in video and article titles. - Example: 서울에서 지하철 타기
Romanization: seo-u-re-seo ji-ha-cheol ta-gi
Translation: Taking the subway in Seoul.
This is common in travel-guide titles. - Example: 한국어 발음 연습하기
Romanization: han-gu-geo ba-reum yeon-seu-pa-gi
Translation: Practicing Korean pronunciation.
「연습하기」works like the title of a learning task.
What Is the Difference Between 「-기」 and 「-(으)ㅁ」?
| Comparison | -기 | -(으)ㅁ |
| Core function | Nominalizes an action | Nominalizes a fact or result |
| Register | Common in conversation, titles, and lists | Common in writing, notices, and formal documents |
| Common situations | To-do items, wishes, preferences | Reports, notices, formal statements |
| Common combinations | 좋아하다、어렵다、쉽다 | 확인됨、알림、밝힘 |
| Common mistake | Can sound too conversational in a formal notice | Can sound too stiff in an everyday list |
▌To-Do Lists and Titles Usually Use 「-기」
❌ Too formal: 사진 정리함
✅ Natural: 사진 정리하기
In lists and to-do items, 「-기」sounds more natural than 「-(으)ㅁ」 and reads like an action to be carried out.
▌Formal Notices Often Use 「-(으)ㅁ」
❌ Too conversational: 예약 취소하기을 알려드립니다.
✅ Correct: 예약이 취소되었음을 알려드립니다.
Formal notifications often use 「-(으)ㅁ」 to package a fact, giving the expression a more formal tone than 「-기」.
「-기」 in Everyday Korean: How Is It Used in Notes and Calendars?
When Koreans write to-do lists, they do not necessarily use complete sentences. Forms such as 「공부하기」「청소하기」「예약 확인하기」 are very common. They are not conversational sentence endings but highly functional shorthand formats.
▌Situation ①｜Organizing a Travel To-Do List
A：여행 전에 할 일 뭐가 있어요?
yeo-haeng jeo-ne hal il mwo-ga i-sseo-yo
What do you need to do before the trip?
B：숙소 예약 확인하기, 환전하기, 지도 저장하기요.
suk-so ye-yak hwa-gin-ha-gi hwan-jeon-ha-gi ji-do jeo-jang-ha-gi-yo
Confirm the accommodation reservation, exchange money, and save the map.
📌 Grammar Point: Actions in a list are nominalized with 「-기」, making them concise and natural.
▌Situation ②｜Planning a Study Schedule
A：오늘 한국어 공부는 뭐 할 거예요?
o-neul han-gu-geo gong-bu-neun mwo hal geo-ye-yo
What are you going to study in Korean today?
B：발음 연습하기랑 드라마 대사 따라 읽기요.
ba-reum yeon-seu-pa-gi-rang deu-ra-ma dae-sa tta-ra il-gi-yo
Practice pronunciation and read along with lines from Korean dramas.
📌 Grammar Point: Both 「연습하기」 and 「읽기」 turn actions into study items.
Cultural Notes:
- Korean notes, YouTube titles, and blog subheadings often use 「-기」 because it is short, clear, and action-oriented.
- 「-기」 does not necessarily function as a formal noun. It often simply turns an action into a task.
- When a formal notice needs to express that “something has been confirmed” or to formally notify someone of a fact, 「-(으)ㅁ」 is more commonly used and gives the expression a stiffer tone.
How Does Korean 「-기」 Compare with Japanese 「〜こと」?
◆ Similar grammar: Japanese 「〜こと」
Japanese 「〜こと」 can also nominalize a verb, as in 「勉強すること」 and 「旅行すること」. Like Korean 「-기」, it allows an action to function as the subject or object of a sentence.
- Example: 早く起きることは難しいです。
Kana: はやくおきることはむずかしいです。
Translation: Getting up early is difficult.
This is close to the Korean 「일찍 일어나기가 어려워요」. - Example: 韓国語を勉強することが好きです。
Kana: かんこくごをべんきょうすることがすきです。
Translation: I like studying Korean.
This is close to the Korean 「한국어 공부하기를 좋아해요」.
◆ Core difference from 「-기」:
Japanese 「〜こと」 is often used within complete sentences. Korean 「-기」, in addition to being used in complete sentences, also appears extensively in shorthand formats such as lists, headings, and calendars.
If you want to bring Korean into your everyday life, small grammar points like this one, which appears in calendars and phone notes, are more practical than they may seem. When writing out your daily plans in a notebook, you do not need to force yourself to produce precise, perfect long sentences. Simply use 「-기」 to turn the actions you want to do into individual list items, and the result will read much more like the way Koreans actually write in everyday life.
Common FAQs
「-기」 is a nominalizing ending that turns a verb into a noun-like form. For example, 「먹기」 means “the act of eating,” while 「공부하기」 means “the act of studying.”
Yes, and it is very common. Expressions such as 「예약 확인하기」「사진 정리하기」「세탁하기」 are similar to writing “confirm reservation,” “organize photos,” and “do laundry” on an English to-do list.
「-기」 is commonly used in conversation, titles, lists, and general nominalization, while 「-(으)ㅁ」 is more formal and is often used in notices, reports, or written notifications.
Both can nominalize an action, but 「공부하기」 feels more like an activity or task, while 「공부하는 것」 feels more like describing “the act of studying” as a concrete piece of content.
No. 「-기」 attaches directly to the stem and does not require different forms based on the final consonant, unlike 「-(으)ㄹ」. 하다 verbs usually become 「하기」.