Verbs/adjectives have specific conjugation when they come before nouns to describe the noun. Often, you see the noun-modifying forms with 거(것): thing, the fact that…, the act of~.

• This is the most commonly used way of nominalization: changing verbs to nouns.
• Used for hobby, habit, preference, dream, wish, resolution, etc. = ~ing

Verbs before nouns

PRESENT TENSE: verb stem~는 + noun

읽다 to read: 읽는 + noun                                  reading: 읽는 거
[example] 저는 책 읽는 거(를) 좋아해요. I like reading.

먹다 to eat:                    + noun                        eating: 먹는 거                                
[예] 저는 먹는 거(를) 좋아해요. I like eating.                

자다 to sleep:                    + noun                     sleeping:  자는 거
                           [예] 저는 자는 거(를) 좋아해요. I like sleeping.                                                                                               

PAST TENSE: verb stem~(으)ㄴ + noun [C 은/Vㄴ]      

읽다 to read: 읽은 + noun                                 the book I read yesterday: 어제 읽은 책
[예] 어제 읽은 책(이) 엄청 재미있었어요.
The book I read yesterday was really fun.

먹다 to eat: 먹은 + noun                        the thing I ate(what I ate):  어제 먹은 거                                             [예] 어제 먹은 거 진짜 맛있었어요.
What we ate yesterday was delicious.

자다 to sleep:  잔 + noun                     the hotel I slept: 잔 호텔
[예] 여기가 제가 잔 호텔이에요.
This is the hotel I slept(stayed).

PROBABILITY/PROSPECTIVE: verb stem~(으)ㄹ + noun [C 을/Vㄹ]

= N to~ (things to do, something to eat, places to go, etc.)

먹다 to eat:  먹을  + noun                thing to eat (something to eat):  먹을 거
                   [예] I’m hungry. Is there something to eat? = 배고파. 먹을 거 있어?

가다 to go: 갈 + noun             places to go: 갈 곳*
*곳(place): only used with a modifier before it, not by itself.
[예] In Seoul, there are many places to go. = 서울에는 갈 곳이 많아요.

Adjectives before nouns

adjective stem~(으)ㄴ + noun C 은/V ㄴ

좋다 to be good: 좋은 + noun                a good person: 좋은 사람
나쁘다 to be bad: 나쁜 + noun               a bad person: 나쁜 사람

Adjectives don’t have to conjugate differently for past or future tenses. This is the same in English:
S/he is a good person.
S/he was a good person.
S/he will be a good person.

BUT, when used with 것 같다 (it seems) to guess about the past such as “I think it was good/bad”, you use: ~았/었던 것 같아요.

좋다 – present 좋아요 – past 좋았어요: Keep the past tense suffix 았 and change 어요 to 던
= 좋았던 것 같아요. It seems like it was good. (I think it was good.)

나쁘다 – present 나빠요 – past 나빴어요: 나빴던 것 같아요. I think it was bad.

Irregular Conjugations

ㄹ irregular              ㄹ drops, and you treat it as a vowel ending

(V.) 살다 to live                사 + (으)ㄴ/는/(으)ㄹ = 산/사는/살
The house I lived before: 전에 산 집
The house I live now: 지금 사는 집
The house I will live next year: 내년에 살 집

(V.) 알다 to know            아 + (으)ㄴ/는/(으)ㄹ = 안/아는/알
The person I know: 아는 사람
I think I know (guessing/probably): 알 것 같아요.

(Adj.) 멀다 to be far           머 + (으)ㄴ = 먼
A far away place: 먼 곳

(Adj.) 길다 to be long         기 + (으)ㄴ = 긴
Long hair: 긴 머리

ㅂ irregular
ㅂ -> 우 when followed by ‘ㅇ’ like (으)ㄴ/(으)ㄹ/어요

(not all ㅂ are irregular: dictionary gives conjugation examples)

(V.) 줍다 to pick sth. up PRESENT ~는: no change = 줍는
쓰레기 줍는 봉사활동: trash picking volunteer
PAST ~(으)ㄴ: ㅂ becomes 우 = 주운
어제 주운 돈: money I picked up (somewhere) yesterday
PROBABILITY/PROSPECTIVE ~(으)ㄹ: ㅂ becomes 우 = 주울
오늘은 주울 쓰레기가 별로 없어요: There’s not much trash to pick up today.

(Adj.) 맵다 to be spicy        ~(으)ㄴ: ㅂ becomes 우 = 매운
Spicy food: 매운 음식
PROBABILITY/PROSPECTIVE ~(으)ㄹ: ㅂ becomes 우 = 매울 I think it will be too spicy. 너무 매울 것 같아요.

있다/없다                 PRESENT: ~는 + N

재미있는 영화(a fun movie)
맛있는 거(something delicious) 먹고 싶어요. 저는 집에 있는 거(staying home) 좋아해요.
지금 집에 없는 거 같아요. (I think s/he is not home now.)