This is the 3466th most frequent Korean word.
떨어지며
"Falling" or "dropping."
떨어지며 in this context links the falling of leaves to the arrival of autumn, indicating a simultaneous occurrence.
나뭇잎이 떨어지며 가을이 찾아온다.
The leaves fall, and autumn arrives.
떨어지며 here connects the action of snow falling to the result of the world becoming white.
눈이 하늘에서 떨어지며 세상을 하얗게 만든다.
Snow falls from the sky, turning the world white.
떨어지며 depicts the act of falling as simultaneous with the emission of a loud sound, indicating a coinciding event.