This is the 10262nd most frequent Spanish word.
comen
"Comen" means "they eat."
In this sentence, the word 'comen' is the third person plural conjugation of the verb 'comer' in the present tense, referring to the action of eating carried out by 'ellos'.
Ellos comen frutas todos los días.
They eat fruits every day.
'Comen' is again used as the base verb for present action and it refers to the subject in the third person plural, questioning their frequent action of eating during the party.
¿Por qué comen tanto durante la fiesta?
Why do they eat so much during the party?
Here, 'comen' describes the habitual eating action of birds, emphasizing their dietary behavior necessary for survival in the present tense.