This is the 5962nd most frequent Spanish word.
viajan
"Viajan" means "they travel" in English.
Here, 'viajan' is used as the present tense form of the verb 'viajar,' conjugated for the third person plural. It describes an action performed by 'ellos'—indicating their travel activity in the present or regularly.
Ellos viajan a España todos los veranos.
They travel to Spain every summer.
In this sentence, 'viajan' again reflects the present tense plural, describing a recurring event or general habit in the given context—traveling.
Cuando viajan, suelen quedarse en hoteles pequeños.
When they travel, they usually stay in small hotels.
Here, 'viajan' appropriately describes the action of travel as it pertains to the subject 'los turistas' (the tourists), ensuring congruency in tense and number.