Verbseoul.
하다 verb

급감하다 conjugation (geupgamhada, to drop/decrease rapidly)

To say to drop/decrease rapidly politely in the present tense, use 급감해요 (geup-gahm-hae-yoh) · geupgamhaeyo. Below is the full conjugation of 급감하다 across the three tenses and three everyday speech levels.

Grammar note (하다 verb): 하다 verbs are formed with a Sino-Korean noun + 하다 (e.g. 공부하다 = study + do). 하다 conjugates irregularly: the ㅏ in 하 contracts with the -아/-어 suffix to give 해 (not *하어). Present polite: 해요; past polite: 했어요. The formal ending is 합니다 (not *하습니다). Most noun+하다 compounds follow this pattern uniformly. See all 하다 verbs →

Conjugation table

pron. = pronunciation guide  · RR = Revised Romanization

Highlighted = where the stem changes

TenseCasual (반말)Polite (요)Formal (합니다)
Present
급감해
geup-gahm-hae
geupgamhae
급감해요
geup-gahm-hae-yoh
geupgamhaeyo
급감합니다
geup-gahm-hahm-nee-dah
geupgamhamnida
Past
급감했어
geup-gahm-hae-ssuh
geupgamhaesseo
급감했어요
geup-gahm-hae-ssuh-yoh
geupgamhaesseoyo
급감했습니다
geup-gahm-hae-sseum-nee-dah
geupgamhaesseumnida
Future
급감할 거야
geup-gahm-hahl guh-yah
geupgamhal geoya
급감할 거예요
geup-gahm-hahl guh-yae-yoh
geupgamhal geoyeyo
급감할 겁니다
geup-gahm-hahl guhm-nee-dah
geupgamhal geomnida

Other useful forms

Honorific / Command Polite (-(으)세요)
급감하세요
geup-gahm-hah-sae-yoh
geupgamhaseyo
Suggestion / Let's Polite (요)
급감해요
geup-gahm-hae-yoh
geupgamhaeyo
Question Polite (요)
급감해요?
geup-gahm-hae-yoh-?
geupgamhaeyo?
Connective "and" — (고)
급감하고
geup-gahm-hah-goh
geupgamhago
Conditional "if" — (면)
급감하면
geup-gahm-hah-myuhn
geupgamhamyeon
Progressive (고 있어요)
급감하고 있어요
geup-gahm-hah-goh ee-ssuh-yoh
geupgamhago isseoyo
Want to (고 싶어요)
급감하고 싶어요
geup-gahm-hah-goh shee-puh-yoh
geupgamhago sipeoyo
Can / Able to ((으)ㄹ 수 있어요)
급감할 수 있어요
geup-gahm-hahl soo ee-ssuh-yoh
geupgamhal su isseoyo
Because / So (아/어서)
급감해서
geup-gahm-hae-suh
geupgamhaeseo
Noun form — (기)
급감하기
geup-gahm-hah-gee
geupgamhagi
Noun form — (음)
급감함
geup-gahm-hahm
geupgamham