Adjectives · 하다 word

약하다 conjugation

to be weak · yakada · sounds like [야카다]

Short answer: “Weak” in Korean is 약하다 (yakada). Polite present: 약해요 (yakaeyo); past: 약했어요 (yakaesseoyo); future: 약할 거예요. It is a 하다 adjective: 하 + 아/어 always becomes 해.

Present약해요[야캐요] · yakaeyo
Past약했어요[야캐써요] · yakaesseoyo
Future약할 거예요[야칼 꺼예요] · yakal geoyeyo
Negative안 약해요[안 야캐요] · an yakaeyo

Opposite: 강하다 — to be strong

약하다 in sentences

저는 술에 약해요.I can’t hold my drink.
약한 불에서 끓이세요.Simmer it over a low heat.

All forms of 약하다

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	약해요	[야캐요]	yakaeyo
formal-(스)ㅂ니다	약합니다	[야캄니다]	yakamnida
casual-아/어	약해	[야캐]	yakae
plain (written)-다	약하다	[야카다]	yakada
formal question-(스)ㅂ니까?	약합니까?	[야캄니까]	yakamnikka?

Past
Form	Korean	Sounds like	Romanized
polite-았/었어요	약했어요	[야캐써요]	yakaesseoyo
formal-았/었습니다	약했습니다	[야캗씀니다]	yakaetseumnida
casual-았/었어	약했어	[야캐써]	yakaesseo
plain (written)-았/었다	약했다	[야캗따]	yakaetda

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

Negative
Form	Korean	Sounds like	Romanized
not (short)안 …	안 약해요	[안 야캐요]	an yakaeyo
did not안 …았/었어요	안 약했어요	[안 야캐써요]	an yakaesseoyo
not (long)-지 않아요	약하지 않아요	[야카지 아나요]	yakaji 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	약하세요	[야카세요]	yakaseyo
honorific — past-(으)셨어요	약하셨어요	[야카셔써요]	yakasyeosseoyo
honorific — formal-(으)십니다	약하십니다	[야카심니다]	yakasimnida

Connecting
Form	Korean	Sounds like	Romanized
… and-고	약하고	[야카고]	yakago
… so / and then-아/어서	약해서	[야캐서]	yakaeseo
if …-(으)면	약하면	[야카면]	yakamyeon
… but-지만	약하지만	[야카지만]	yakajiman
because …-(으)니까	약하니까	[야카니까]	yakanikka
… and / but (background)-(으)ㄴ데	약한데	[야칸데]	yakande
even if …-아/어도	약해도	[야캐도]	yakaedo
while …-(으)면서	약하면서	[야카면서]	yakamyeonseo

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	약한	[야칸]	yakan
(that) will …-(으)ㄹ	약할	[야칼]	yakal

Useful patterns
Form	Korean	Sounds like	Romanized
can be …-(으)ㄹ 수 있어요	약할 수 있어요	[야칼 쑤 이써요]	yakal su isseoyo
cannot be …-(으)ㄹ 수 없어요	약할 수 없어요	[야칼 쑤 업써요]	yakal su eopseoyo
have to be …-아/어야 해요	약해야 해요	[야캐야 해요]	yakaeya haeyo
it’s OK if it’s …-아/어도 돼요	약해도 돼요	[야캐도 돼요]	yakaedo dwaeyo
…ly (adverb)-게	약하게	[야카게]	yakage
becomes …-아/어지다	약해져요	[야캐저요]	yakaejeoyo
…ing (noun)-기	약하기	[야카기]	yakagi

How 약하다 changes

Every 하다 word works the same way: 하 + 여 becomes 해 → 약해요, 약했어요. With other endings 하 stays as it is: 약합니다, 약하면.

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

Questions

How do you say “weak” in Korean?

“Weak” is 약하다 (yakada), pronounced [야카다]. In a sentence: 저는 술에 약해요. — I can’t hold my drink.

What is the past tense of 약하다?

약했어요 (yakaesseoyo) is the polite past tense of 약하다 (“to be weak”). Formal: 약했습니다; casual: 약했어.

How do you say 약하다 politely?

Everyday polite: 약해요 (yakaeyo). Formal: 약합니다. Casual, with close friends: 약해.

How do you say “not weak” in Korean?

안 약해요 or 약하지 않아요. Both mean the same; the first is more common in speech.

Is 약하다 irregular?

No. Every 하다 word works the same way: 하 + 여 becomes 해 → 약해요, 약했어요. With other endings 하 stays as it is: 약합니다, 약하면.

More 하다 words like 약하다

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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