This is the 3615th most frequent Swedish word.
fylldes
"Fylldes" means "was filled" in English.
The word 'fylldes' is used here as the past passive form of 'fylla', indicating that the bottle underwent the action of being filled.
Flaskan fylldes med vatten av personen.
The bottle was filled with water by the person.
In this sentence, 'fylldes' describes the room passively receiving the state of being filled by joy.
Rummet fylldes med glädje när alla började sjunga.
The room was filled with joy when everyone started singing.
Here, 'fylldes' denotes the ocean's state being changed by the action of accumulating debris, indicating its passive form usage.