줄어들어요 · 줄어들었어요 · 줄어들 거예요 · 줄어드는 (+noun) (ㄹ drops)
to decrease, to shrink, to diminish
Example
시골에 사는 젊은 사람이 점점 줄어들고 있어요.
The number of young people living in the countryside is gradually shrinking.
Word parts
줄다 (to decrease) + 들다 (to go in): shrinking inward.