Learn Hardcore Croatian: Živim blizu parka, a ona živi u gradu. - I live near the park, and she lives in the city.

u with a static location takes the locative case, so you get u gradu (“in the city”). With motion into a place, u takes the accusative: u grad (“to the city”).

Static: Radim u gradu. (I work in the city.)
Motion: Idem u grad. (I’m going to the city.)

What does the conjunction a do here? Could I use i or ali instead?

a signals a mild contrast or comparison, often translated as “and/while/whereas.”
i is a plain “and” that just adds information, with little or no contrast.
ali is a stronger “but.” In this sentence, a nicely contrasts “I live near the park” with “she lives in the city.” You could use i, but you’d lose the contrast. ali would sound too adversative.

Why do we explicitly say ona but not ja?

Croatian is a “pro‑drop” language: subject pronouns are often omitted because verb endings show the person. Živim already tells us “I live,” so ja is unnecessary. Ona is included to make the contrast clear after a (“whereas she”), and to avoid ambiguity about who the second subject is.

How is živjeti conjugated in the present, and why are the endings different in živim and živi?

The present stem is živ-. Endings differ by person:

ja živim
ti živiš
on/ona/ono živi
mi živimo
vi živite
oni/one/ona žive

Could I change the word order, like Blizu parka živim or Ona u gradu živi?

Yes. Croatian word order is flexible. Fronting an element gives it emphasis:

Blizu parka živim emphasizes the location.
Ona u gradu živi emphasizes “she” or “in the city.” All are grammatically correct; the basic order in the original is the most neutral.

What’s the difference between blizu and u blizini?

Both mean “near/close to.” blizu is a preposition that takes the genitive (blizu parka). u blizini literally means “in the vicinity (of)” and also takes the genitive (u blizini parka). u blizini can sound a bit more formal or descriptive; blizu is shorter and very common.

Are there other common ways to say “near the park”?

Yes:

pored/pokraj/kraj parka (beside/by the park; genitive)
kod parka (by/at the area of the park; genitive)
uz park (along/next to the park; accusative, often implying adjacency)

Why is it u gradu and not na gradu? When do I use u vs na?

Generally, u = “in,” na = “on/at,” but usage is idiomatic in places:

u gradu (in the city)
na selu (in the countryside)
na moru (at the seaside)
u školi (at/in school)
na poslu (at work)
u bolnici (in the hospital)
na ulici (out on the street) So “city” uses u, “countryside” and “sea” use na, etc.

Do I need the comma before a?

Yes. In standard Croatian, you put a comma before a when it connects independent clauses, as in this sentence.

How do I pronounce Ž in Živim?

Like the “s” in English “measure” or the “g” in “mirage” (the “zh” sound). So Živim ≈ “ZHee-veem.”

I often see people type Zivim without the special letter. Is that acceptable?

Not in proper writing. Always use Croatian diacritics: č, ć, ž, š, đ. Typing without them is common in casual texting but is orthographically incorrect.

Where are the words for “the” or “a”? Shouldn’t it be “the park” or “a city”?

Croatian has no articles. park and grad can be understood as “the park/city” or “a park/city” from context. Here, English would naturally use “the park” and “the city.”

Why is grad spelled gradu here? What are the cases of grad?

gradu is the locative (also the dative) singular form of grad. A quick overview (singular):

Nominative: grad
Genitive: grada
Dative/Locative: gradu
Accusative: grad
Instrumental: gradom

How would the sentence change if we were talking about movement?

You’d use the accusative with u for motion: Idem u grad (I’m going to the city). For “toward the park,” you could say prema parku (dative) or k parku (less common), while “near the park” as a destination is often phrased as Idem blizu parka in casual speech, though more precise is Idem do parka (“I’m going up to the park”).

Can grad mean both “city” and “town”? Is there a different word for “town”?

Yes, grad covers both “city” and “town” in everyday use. If you want to stress smallness, you can say mali grad (small town) or gradić (little town). The contrast is more about size/context than different base words.