Becoming with -아/어지다: 예뻐지다, 좋아지다

An adjective describes a state: 예쁘다 means "is pretty," 좋다 means "is good." But often you don't want to say something is a certain way — you want to say it became that way, that it changed. Korean does this with -아/어지다: 예뻐지다 ("become pretty"), 좋아지다 ("get better"), 커지다 ("get bigger"). The reframe is the whole lesson: a static quality is turned into a change on a timeline, and with that change the word stops behaving like an adjective and starts behaving like an action verb. This crossing of the verb/adjective divide is the clean capstone of the whole "adjective → verb shift" group.

The formation: -아/어 form + 지다

Take the adjective's -아/어 form — the exact same harmony form you'd use for the present -아/어요 — and add 지다. Every rule you already know for choosing 아 vs 어, for the 으-drop, and for 하다 carries straight over.

The present-tense 져요 is just 지 + 어요 contracting (ㅣ + ㅓ → ㅕ), exactly like any other verb whose stem ends in ㅣ. If you can already make 예뻐요, you can make 예뻐져요 — you're just gluing 지다 onto the form you already had. For the 으-drop that gives 예뻐 and 커, see the 으-drop page.

The reframe: state → change, adjective → verb

Here's the pivot. 예쁘다 names a quality that just is. But 예뻐지다 adds a before and after — there was a time when it wasn't pretty, and now (or later) it is. That timeline is what verbs are for. So the moment an adjective takes -지다, it becomes an action verb, and it takes verb endings from then on:

• Progressive: 예뻐지고 있어요 ("is getting prettier") — the -고 있다 progressive is a verb-only form, impossible on a plain adjective.
• Present attributive: 예뻐지는 얼굴 ("a face that's getting prettier") — the verb ending -는, not the adjective -(으)ㄴ.
• Past: 좋아졌어요 ("got better").

This is the payoff of the whole group. The bare adjective 예쁘다 takes -(으)ㄴ for its present modifier (예쁜 얼굴 — see the -(으)ㄴ vs -는 divide); but once it's 예뻐지다, it crosses over and takes -는 (예뻐지는 얼굴). Same root, opposite ending — because the word class changed.

Why -지다 and not just 되다

English "become" makes learners reach for 되다, but the two tools have different jobs. -아/어지다 attaches to an adjective and expresses a gradual change of quality — get better, get bigger, become quiet. 되다 pairs with a noun (+ 이/가) and means "become a [thing]" — 의사가 되다 ("become a doctor"), 어른이 되다 ("become an adult").

Trying to force "become pretty" through 되다 — ×예쁘게 되다 — sounds stiff and translated; the idiomatic choice is the -아/어지다 that this page is about. (There is a -게 되다 construction, but it means "come to be (through circumstances)" and carries a different nuance — that's a separate topic, -게 되다 vs -아/어지다.) For "become a doctor," on the other hand, only 되다 works — you can't say ×의사아지다.

Common Mistakes

1. Keeping the adjective attributive after -지다 — ×예뻐지은. 지다 is a verb now: -는.

2. Forcing "become + adjective" through 되다 — ×예쁘게 됐어요. Use -아/어지다 for a change of quality.

3. Attaching 지다 to the dictionary stem instead of the -아/어 form — ×좋지다, ×크지다. It builds on 좋아, 커.

4. Using 되다 with a noun but the wrong particle — ×의사를 됐어요. 되다 takes 이/가, not 을/를.

Key Takeaways

• -아/어지다 turns an adjective (a state) into an inchoative verb (a change): 좋다 → 좋아지다, 예쁘다 → 예뻐지다, 크다 → 커지다, 많다 → 많아지다, 조용하다 → 조용해지다.
• Build it on the adjective's -아/어 form (the same one you use for -아/어요), then conjugate 지다 as a verb (present 져요).
• Once it takes -지다 it crosses the verb/adjective divide: verb endings apply — progressive 예뻐지고 있어요, present modifier 예뻐지는 (-는, not ×예뻐지은).
• Use -아/어지다 for "become + adjective" (a quality); use noun + 이/가 되다 for "become + noun" (의사가 되다). ×예쁘게 되다 is stiff.