This is the 12348th most frequent Spanish word.
llenaron
"Filled" (past tense of "fill").
Here, the word 'llenaron' is used to describe the action of filling a container, specifically the tank of a car with fuel.
Llenaron el tanque del coche antes de salir de viaje.
They filled the car's tank before starting the trip.
In this example, 'llenaron' expresses the idea of occupying or filling a space, in this case the room, with something abstract, like presence.
Los invitados llenaron la habitación con su presencia.
The guests filled the room with their presence.
Here, 'llenaron' metaphorically indicates that the days were imbued or made abundant with joy, describing an emotional state caused by someone's visit.