Learn Italian: Tu sei uno studente nuovo.

In Italian, the masculine word for a or an is usually un. But because studente starts with an s followed by another consonant (the t), you must use uno. This rule exists to make the words flow better and be easier to pronounce!

Why does nuovo come after studente?

In English, we put the adjective before the noun (new student). In Italian, most descriptive adjectives like nuovo (new) are placed immediately after the noun they describe.

How do we know to use nuovo and not nuova?

Adjectives need to match the noun in gender and number. Even though studente ends in an e, it is a masculine noun. Therefore, the adjective takes the masculine singular ending -o, making it nuovo.

Do I always have to use Tu before sei?

No, you can drop it and just say Sei uno studente nuovo. Since the verb sei specifically means you are, the word Tu is optional and is usually only kept for emphasis.