Learn Italian: Chi incontri oggi in centro? - Who are you meeting downtown today?

In English, we sometimes use 'whom' when the person is receiving the action (you are meeting whom). In Italian, you just use chi for both 'who' and 'whom'. It never changes form!

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

It is built right into the verb! Incontri is the 'you' form of the verb incontrare (to meet). Since the verb ending already tells us who is doing the action, Italian usually drops the word tu (you).

The translation says 'are you meeting', but isn't incontri just the simple present tense?

Yes! In Italian, you can use the simple present tense to talk about plans for the near future. This is very common when you include a time word like oggi (today) or domani (tomorrow).

Why is it in centro instead of using an article like nel centro?

For certain common places in town, Italians use in without a definite article ('the'). In centro (downtown/in the city center) is a set phrase you can memorize, just like in banca (at the bank) or in pizzeria (at the pizzeria).