Я народився в маленькому місті, а моя дружина народилася біля моря.

Because Ukrainian past tense agrees with the gender of the subject.

• Я народився = I was born (said by a man)
• Я народилася = I was born (said by a woman)
• моя дружина народилася = my wife was born because дружина is feminine

So in this sentence, the speaker is male, and the wife is female.

-ся is a reflexive particle. In many Ukrainian verbs, it is part of the standard verb form and does not always translate directly into English.

With народитися, the full verb means to be born. So:

• народитися = to be born
• народився = was born (masculine)
• народилася = was born (feminine)

Even though -ся historically relates to reflexive meaning, in this verb you should learn it as part of the whole word.

Because after в meaning in, Ukrainian uses the locative case for location.

• місто = city/town
• в місті = in the city/town

The adjective must match too:

• маленьке місто = a small city/town
• в маленькому місті = in a small city/town

So both words change because they are in the locative.

місті is the locative singular form of місто.

The adjective маленький must agree with the noun in:

• gender
• number
• case

Since місто is neuter singular and here it is in the locative, the adjective becomes маленькому.

So:

• nominative: маленьке місто
• locative: в маленькому місті

Because біля means near / by, and it requires the genitive case.

• море = sea
• біля моря = near the sea

So море changes to моря because it is in the genitive singular.

They express two different kinds of location:

• в маленькому місті = in a small city
• біля моря = near the sea / by the sea

So the speaker was born inside a town/city, while the wife was born near the sea, not necessarily literally in the sea town itself.

А often links two clauses with a mild contrast or comparison.

Here it works like:

• I was born in a small town, whereas my wife was born by the sea.

Compare:

• і = and, simple addition
• але = but, stronger contrast
• а = and/but, with a contrastive feel

In this sentence, а is very natural because the two birthplaces are being contrasted.

Yes, often it can be omitted because the verb form already shows the person.

• Народився в маленькому місті... can still mean I was born in a small town...

But Я is included for clarity or emphasis, especially at the beginning of a sentence.

So both are possible, but Я is perfectly natural.

Usually no, not in the same way as Я.

• моя дружина = my wife
• дружина alone = wife / the wife

If you omit моя, the meaning becomes less specifically my wife unless the context makes it obvious. So here моя дружина is the normal choice.

Usually, в and у both mean in/to, and Ukrainian often chooses between them for smoother pronunciation.

So you may hear:

• в маленькому місті
• у маленькому місті

Both are possible. The choice often depends on surrounding sounds and rhythm rather than a difference in meaning.

It can mean either city or town, depending on context.

So в маленькому місті could be translated as:

• in a small town
• in a small city

In many contexts, English town sounds more natural if the place is small, but the Ukrainian word itself is місто.

Народитися is normally perfective, and that makes sense because being born is seen as a single completed event.

In this sentence, that is exactly what is needed: a completed event in the past.

So:

• народився / народилася = was born

This is one of those verbs where the perfective form is the normal one for the idea.

She would say:

• Я народилася в маленькому місті...

The rest of the sentence could stay the same if she is talking about her wife, but in the original sentence the first-person form народився tells us the speaker is male.

The main dictionary forms are:

• я = I
• народитися = to be born
• в / у = in
• маленький = small
• місто = city, town
• а = and/but (contrastive)
• мій = my
• дружина = wife
• біля = near, by
• море = sea

This can help you see how the forms in the sentence change because of grammar.

Because Ukrainian often expresses ideas in a more synthetic way, with a single verb form carrying tense and agreement information.

So English:

• I was born

becomes Ukrainian:

• Я народився or Я народилася

The Ukrainian verb already shows:

• past tense
• gender
• number

So there is no separate word for was here.