Adjectives · 하다 word

위험하다 conjugation

to be dangerous · wiheomhada · sounds like [위험하다]

Short answer: “Dangerous” in Korean is 위험하다 (wiheomhada). Polite present: 위험해요 (wiheomhaeyo); past: 위험했어요 (wiheomhaesseoyo); future: 위험할 거예요. It is a 하다 adjective: 하 + 아/어 always becomes 해.

Present위험해요[위험해요] · wiheomhaeyo
Past위험했어요[위험해써요] · wiheomhaesseoyo
Future위험할 거예요[위험할 꺼예요] · wiheomhal geoyeyo
Negative안 위험해요[안 위험해요] · an wiheomhaeyo

Opposite: 안전하다 — to be safe

위험하다 in sentences

여기는 위험해요.It’s dangerous here.
위험한 곳에는 가지 마세요.Don’t go to dangerous places.

All forms of 위험하다

Present
Polite (해요) is the everyday safe choice; formal (합니다) is for news, announcements and work; casual (반말) is for close friends and younger people.
Form	Korean	Sounds like	Romanized
polite-아/어요	위험해요	[위험해요]	wiheomhaeyo
formal-(스)ㅂ니다	위험합니다	[위험함니다]	wiheomhamnida
casual-아/어	위험해	[위험해]	wiheomhae
plain (written)-다	위험하다	[위험하다]	wiheomhada
formal question-(스)ㅂ니까?	위험합니까?	[위험함니까]	wiheomhamnikka?

Past
Form	Korean	Sounds like	Romanized
polite-았/었어요	위험했어요	[위험해써요]	wiheomhaesseoyo
formal-았/었습니다	위험했습니다	[위험핻씀니다]	wiheomhaetseumnida
casual-았/었어	위험했어	[위험해써]	wiheomhaesseo
plain (written)-았/었다	위험했다	[위험핻따]	wiheomhaetda

Future
Form	Korean	Sounds like	Romanized
polite — will probably be-(으)ㄹ 거예요	위험할 거예요	[위험할 꺼예요]	wiheomhal geoyeyo
formal-(으)ㄹ 겁니다	위험할 겁니다	[위험할 껌니다]	wiheomhal geomnida
casual-(으)ㄹ 거야	위험할 거야	[위험할 꺼야]	wiheomhal geoya

Negative
Form	Korean	Sounds like	Romanized
not (short)안 …	안 위험해요	[안 위험해요]	an wiheomhaeyo
did not안 …았/었어요	안 위험했어요	[안 위험해써요]	an wiheomhaesseoyo
not (long)-지 않아요	위험하지 않아요	[위험하지 아나요]	wiheomhaji anayo

Honorific
Add -(으)시- when the subject is someone you respect (a teacher, a customer, an older person) — not yourself.
Form	Korean	Sounds like	Romanized
honorific — present-(으)세요	위험하세요	[위험하세요]	wiheomhaseyo
honorific — past-(으)셨어요	위험하셨어요	[위험하셔써요]	wiheomhasyeosseoyo
honorific — formal-(으)십니다	위험하십니다	[위험하심니다]	wiheomhasimnida

Connecting
Form	Korean	Sounds like	Romanized
… and-고	위험하고	[위험하고]	wiheomhago
… so / and then-아/어서	위험해서	[위험해서]	wiheomhaeseo
if …-(으)면	위험하면	[위험하면]	wiheomhamyeon
… but-지만	위험하지만	[위험하지만]	wiheomhajiman
because …-(으)니까	위험하니까	[위험하니까]	wiheomhanikka
… and / but (background)-(으)ㄴ데	위험한데	[위험한데]	wiheomhande
even if …-아/어도	위험해도	[위험해도]	wiheomhaedo
while …-(으)면서	위험하면서	[위험하면서]	wiheomhamyeonseo

Describing a noun
These go before a noun: “the food (that) I ate”, “a cold day”.
Form	Korean	Sounds like	Romanized
(that is) …-(으)ㄴ	위험한	[위험한]	wiheomhan
(that) will …-(으)ㄹ	위험할	[위험할]	wiheomhal

Useful patterns
Form	Korean	Sounds like	Romanized
can be …-(으)ㄹ 수 있어요	위험할 수 있어요	[위험할 쑤 이써요]	wiheomhal su isseoyo
cannot be …-(으)ㄹ 수 없어요	위험할 수 없어요	[위험할 쑤 업써요]	wiheomhal su eopseoyo
have to be …-아/어야 해요	위험해야 해요	[위험해야 해요]	wiheomhaeya haeyo
it’s OK if it’s …-아/어도 돼요	위험해도 돼요	[위험해도 돼요]	wiheomhaedo dwaeyo
…ly (adverb)-게	위험하게	[위험하게]	wiheomhage
becomes …-아/어지다	위험해져요	[위험해저요]	wiheomhaejeoyo
…ing (noun)-기	위험하기	[위험하기]	wiheomhagi

How 위험하다 changes

Every 하다 word works the same way: 하 + 여 becomes 해 → 위험해요, 위험했어요. With other endings 하 stays as it is: 위험합니다, 위험하면.

How every verb type works → · Why it sounds like that →

Questions

How do you say “dangerous” in Korean?

“Dangerous” is 위험하다 (wiheomhada), pronounced [위험하다]. In a sentence: 여기는 위험해요. — It’s dangerous here.

What is the past tense of 위험하다?

위험했어요 (wiheomhaesseoyo) is the polite past tense of 위험하다 (“to be dangerous”). Formal: 위험했습니다; casual: 위험했어.

How do you say 위험하다 politely?

Everyday polite: 위험해요 (wiheomhaeyo). Formal: 위험합니다. Casual, with close friends: 위험해.

How do you say “not dangerous” in Korean?

안 위험해요 or 위험하지 않아요. Both mean the same; the first is more common in speech.

Is 위험하다 irregular?

No. Every 하다 word works the same way: 하 + 여 becomes 해 → 위험해요, 위험했어요. With other endings 하 stays as it is: 위험합니다, 위험하면.

More 하다 words like 위험하다

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Forms follow 한글 맞춤법 (Korean spelling rules); pronunciation follows 표준 발음법 and romanization follows 국어의 로마자 표기법 (Revised Romanization). Last updated October 16, 2026. How we check