Learn Italian: Lei ha fatto uno sbaglio.

In Italian, the formal word for "you" is Lei (often written with a capital L to tell it apart from lei meaning "she"). Because it acts like a third-person pronoun, it pairs with ha just like "he" or "she" would.

How is ha fatto formed, and what verb does it come from?

Ha fatto is the past tense of fare (to do / to make). Fatto is an irregular past participle. Instead of following the normal "-ato" pattern, fare changes to fatto. It pairs with the helper verb avere, which is why we use ha here.

Does fare always mean "to make"?

Fare can mean either "to do" or "to make" depending on the context. Here, fare uno sbaglio perfectly matches the English phrase "to make a mistake."

Why is the word for "a" uno instead of un in this sentence?

This is a quick reminder of an earlier rule: because sbaglio starts with an "s" followed by another consonant (the letter "b"), it requires the masculine article uno instead of un to make the words flow smoothly when spoken.