This is the 9491st most frequent French word.
débutent
"Débutent" means "begin" or "start" (third person plural of "débuter").
Here "débutent" is used to indicate the starting time of classes, emphasizing their recurring nature.
Les cours débutent à neuf heures chaque matin.
The classes begin at nine o'clock every morning.
In this context, "débutent" is used to describe the beginning of an anticipated event (competitions).
Les compétitions débutent demain au stade municipal.
The competitions start tomorrow at the municipal stadium.
Here "débutent" signifies the commencement of an individual's professional engagement or career.