Learn Croatian: Jesi li izašla sinoć? - Did you go out last night?

In Croatian, yes/no questions often start with a helper verb followed by the question particle li. Here, jesi is the informal "you" form of the verb "to be". When you combine Jesi li with a past tense verb like izašla, it works exactly like saying "Did you..." in English.

Where is the word for "you" in this sentence?

The pronoun ti (you) is completely left out because it is not needed. The helper verb jesi specifically tells us the subject is "you". Croatian frequently drops subject pronouns when the verb itself already makes it completely clear who is doing the action.

How do we know the person being asked is a woman?

The main verb izašla (went out) ends in -a. In the Croatian past tense, the main verb changes its ending based on the gender of the person doing the action. If you were asking a man this exact same question, the verb would take the masculine ending -o, making it Jesi li izašao sinoć?

Where would I put the word "ti" (you) if I really wanted to include it?

If you want to include ti for emphasis (like asking "Did you go out last night?"), it typically goes right after the question particle. You would say Jesi li ti izašla sinoć?