Questions & Answers about Vi ne vidite gdje mi živimo.
Both verbs here come from infinitives ending in -jeti (vidjeti, živjeti). Why do they have an i in their present tense forms (vidite, živimo)?
Most regular verbs that end in -jeti use i in their present tense endings. To conjugate them, you drop the -jeti part from the infinitive and add the standard endings for this group: -im, -iš, -i, -imo, -ite, -e. So, vidjeti becomes vidite (you see), and živjeti becomes živimo (we live).
We already know who is doing the action from the verb endings (-ite and -imo). Why are the pronouns vi and mi included?
You're right that Croatian usually drops subject pronouns because the verb ending tells you who is doing the action! However, speakers keep them when they want to emphasize a contrast. This sentence highlights the opposition between the two groups: You (vi) don't see where we (mi) live.
Why is the negative ne vidite written as two separate words?
For almost all verbs in Croatian, you make them negative simply by placing the word ne in front of the verb, and it is always written as a separate word. It only combines into a single word for a few very common irregular verbs you learned earlier (like nemam for "I do not have").