Learn Hardcore Italian: La settimana diventa lunga.

In Italian, each noun has a designated grammatical gender that doesn’t always match logical gender. Settimana is one such word that is feminine by convention. You typically recognize it by its ending (-a), which usually—but not always—signals the feminine gender in Italian.

Why does the adjective change to lunga instead of lungo?

Adjectives in Italian must match the gender (and number) of the noun they describe. Since settimana is feminine and singular, the adjective must be feminine and singular as well. Hence, we say lunga rather than lungo.

Why do we use the verb diventa here?

The verb diventare means “to become,” and diventa is its third-person singular present tense form. We use it because the sentence describes the ongoing process of a week that “becomes” long. If you want to convey that the week is getting long at this moment, the present tense is appropriate.

Could I say La settimana è lunga instead of La settimana diventa lunga?

Yes, but the meaning changes. La settimana è lunga simply states that the week “is long” as a static fact. La settimana diventa lunga emphasizes that the week “becomes long,” implying a sense of progression or development over time.