Tense theory in Catalan grammar plays a vital role in understanding the temporal aspect of verbs. Catalan, like many Romance languages, has a rich system of verb tenses and moods that express different actions and states in time.

The present tense (present) is used to describe actions occurring in the present moment or habitual actions. The past tense (passat) refers to actions that have already been completed in the past, while the future tense (futur) indicates actions that will happen in the future.

Additionally, we have compound verb tenses that combine auxiliary verbs with the past participle to express more complex ideas. The perfect tense (pretèrit perfet) is used to talk about recent actions that have an impact on the present, while the pluperfect tense (pretèrit plusquamperfet) refers to actions completed before another past action. The future perfect tense (futur anteriror) expresses actions that will be completed before a certain point in the future.

Understanding and correctly using these tenses is essential for effective communication in Catalan. Mastery of tense theory allows speakers to express their thoughts accurately and convey precise temporal information.