Korean -아/어지다 vs -게 되다: Two Ways to Say "Become"

"이상하지고 있어요" — a learner on a daily writing community wrote this about their sleep schedule, trying to say it's becoming strange. Close, but one step got skipped along the way: it should be 이상해지고 있어요. The fix looks small — one changed syllable — but it points at a rule worth locking down: in this "become" sense, 지다 doesn't attach straight to the dictionary stem. It rides on the -아/어 form first.

That slip is really about -아/어지다, the ending Korean uses to say a state is gradually turning into something else. But English "become" covers a second Korean pattern too — -게 되다 — and mixing the two up is exactly the kind of mistake a spellchecker won't catch. Only rereading your own diary and wondering why it sounds slightly off will.

-아/어지다: an adjective drifting toward a new state

-아/어지다 attaches to an adjective stem, using the same -아/어 form you'd use for the past tense — then adds 지다. The adjective supplies the state; 지다 supplies the sense of turning into it.

Adjective	+ -아/어지다	Meaning
이상하다 (strange)	이상해지다	become strange
춥다 (cold)	추워지다	become cold
따뜻하다 (warm)	따뜻해지다	become warm
예쁘다 (pretty)	예뻐지다	become pretty

That table also shows why 이상하지다 doesn't work: 이상하다 is a 하다-adjective, so it needs 하 + 여 → 해 before 지다 can attach — 이상해지다, not 이상하지다. The same logic holds for every adjective here: find the -아/어 form first (the one you'd already use for past tense — 추웠어요, 예뻤어요), then add 지다 to that form, not to the bare dictionary stem.

Two irregulars trip people up the most. 춥다 is a ㅂ irregular (춥 → 추우 → 추워), so it's 추워지다, never 춥어지다. 다르다 (different) is a 르 irregular — the 르 doubles into ㄹㄹ before 아 — giving 달라지다: 요즘 제 하루 루틴이 많이 달라졌어요 (my daily routine has changed a lot lately).

One more thing worth knowing, in a single line: -아/어지다 can also attach to verb stems, but there it does a different job — it builds the passive, not "become" (만들다 → 만들어지다, "to be made"). This post is only about the adjective + become use; the passive is its own topic for another day.

-게 되다: a verb landing on an outcome you didn't choose

-게 되다 attaches to a verb stem — always with 게, no vowel harmony to worry about — and says the subject arrived at doing something, usually because of circumstances rather than a deliberate decision.

• 친구 소개로 그 카페를 알게 됐어요. — Through a friend's introduction, I came to know that café.
• 갑자기 야근이 생겨서 약속을 취소하게 됐어요. — Overtime came up out of nowhere, so I ended up canceling the plans.
• 계속 연습하다 보니까 이해하게 됐어요. — After a lot of practice, I came to understand it.

None of these say the subject decided to know the café, cancel the plans, or understand something. -게 되다 reports the result as something that came about, with circumstances doing most of the work.

The two side by side

	-아/어지다	-게 되다
Attaches to	mostly adjectives	verbs
Says	a state is gradually changing	a situation or action came about
Feel	"becoming ___"	"it turned out that I ___"
Example	날씨가 따뜻해졌어요. (It became warm.)	한국어를 좋아하게 됐어요. (I came to like Korean.)

The trap: forcing -게 되다 onto an adjective

Because both translate as "become," it's tempting to bolt -게 되다 onto an adjective the same way you'd use it with a verb. 바쁘게 되다 is understandable and does show up occasionally, but it reads a little unnatural next to the adjective's own built-in "become" form — 바빠지다 already does that job on its own. Stacking both together, 바빠지게 되다, is redundant and best avoided. When the thing changing is a state described by an adjective, -아/어지다 is usually the safer, more natural default; save -게 되다 for verbs and for outcomes that circumstances handed you.

Try it in tonight's entry

Pick one thing that's been changing lately and one thing that happened to you because of circumstances, not choice — then write both:

• 요즘 날씨가 갑자기 쌀쌀해졌어요.
• 일이 많아서 잠자는 시간이 늦어졌어요.
• 팀이 바뀌면서 새 프로젝트를 맡게 됐어요.

If the sentence is about a state slowly shifting, reach for -아/어지다. If it's about landing in a situation you didn't plan, -게 되다 is the one doing the work.