
Examples:
예쁘다 ---> 예뻐지다
to be pretty --- to become pretty
조용하다 --- 조용해지다
to be quiet--- to become quiet
Some adjectives are used so frequently in the 여/야지다 construction that they are mostly considered as independent verbs and have direct English translations too.
1.
다르다 : to be different
달라지다 : to change (to become different)
여기 많이 달라졌어요.
2.
좋다 : to be good
좋아지다 : to improve, to get better
한국말 실력이 많이 좋아졌어요.
3.
많다 : to be multiple
많아지다 : to increase
한국어 공부하는 사람이 많아졌어요.
4.
없다 : to not exist, to not have
없어지다 : to disappear
내 가방이 아까 여기 있었는데 없어졌어요.