Моя донька читає книгу в вітальні.

Because моя has to agree with донька (daughter).

In Ukrainian, possessive words like my change their form to match the gender, number, and case of the noun:

• мій = masculine singular
• моя = feminine singular
• моє = neuter singular
• мої = plural

Since донька is feminine singular, the correct form is моя донька.

Because книгу is in the accusative case, which is used here for the direct object of the verb читає (reads / is reading).

• книга = nominative singular, the dictionary form
• книгу = accusative singular

In this sentence, the daughter is reading a book / the book, so book is the thing directly affected by the action. That is why Ukrainian uses the accusative:

• Моя донька читає книгу.

A very common pattern:

• feminine nouns ending in -а often change to -у in the accusative singular.

For example:

• газета → газету
• машина → машину
• книга → книгу

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

• вітальня = living room, nominative form
• в вітальні = in the living room, locative form

So:

• вітальня = the living room
• в вітальні = in the living room

Many feminine nouns ending in -я change to -і in the locative singular:

• кухня → у кухні
• спальня → у спальні
• вітальня → у / в вітальні

Yes, it is normal. The first в is the preposition in, and the second в is simply the first letter of вітальні.

So they are two different words:

• в = in
• вітальні = living room (locative form)

That said, Ukrainian often alternates between в and у for smoother pronunciation. So you may also hear:

• Моя донька читає книгу у вітальні.

This means exactly the same thing. Very often, speakers choose в or у based on what sounds more natural in context.

Читає is present tense, third person singular, from the verb читати (to read).

So it means:

• she reads
• she is reading

Ukrainian does not normally have a separate form like English is reading. The same present-tense form can cover both a general present and an action happening now, depending on context.

Conjugation of читати in the present:

• я читаю = I read / am reading
• ти читаєш = you read / are reading
• він/вона/воно читає = he/she/it reads / is reading
• ми читаємо = we read / are reading
• ви читаєте = you read / are reading
• вони читають = they read / are reading

Because Ukrainian usually expresses both simple present and present continuous with the same present-tense verb form.

So:

• читає can mean reads
• читає can also mean is reading

Context tells you which meaning is intended. In a sentence like Моя донька читає книгу в вітальні, English would often translate it as My daughter is reading a book in the living room, but Ukrainian does not need a separate continuous construction.

Because Ukrainian has no articles.

So книгу can mean:

• a book
• the book

And в вітальні can mean:

• in a living room
• in the living room

Usually the exact meaning is clear from context. If a speaker wants to be more specific, Ukrainian can use other words, word order, or context rather than articles.

This is a major difference from English.

Yes, the sentence can be rearranged. Ukrainian word order is more flexible than English because case endings show grammatical roles.

The neutral, straightforward order here is:

• Моя донька читає книгу в вітальні.

But other orders are possible for emphasis, for example:

• У вітальні моя донька читає книгу.
  Emphasis on in the living room.

• Книгу читає моя донька в вітальні.
  Emphasis on the book or contrast.

Even though word order can change, the case endings help show who is doing what:

• донька is the subject
• книгу is the object

In Ukrainian, the subject is often identified by the nominative case and by verb agreement.

Here:

• донька is in the nominative form
• читає is third person singular, matching донька

Meanwhile:

• книгу is accusative, so it is the direct object

Because Ukrainian uses case endings, it does not depend on word order as heavily as English does.

Because читати is imperfective, and that is the normal choice for an ongoing or general present action.

• читати = to read, be reading, read in general
• прочитати = to read through, finish reading

In Ukrainian, perfective verbs like прочитати usually do not have a true present-tense meaning. Their present-looking forms usually refer to the future.

So:

• Моя донька читає книгу = My daughter is reading a book / reads a book
• Моя донька прочитає книгу = My daughter will read / will finish reading the book

That is why читає is the natural form here.

In this sentence, в вітальні most naturally means in the living room.

The preposition в / у can sometimes correspond to English in, at, or into, depending on the case and context:

• в кімнаті = in the room
• в школі = at school / in school
• в кімнату = into the room

Here, because вітальні is in the locative case, it shows location, so in the living room is the best match.

In донька, the ь is the soft sign. It does not make its own sound, but it softens the consonant before it.

So in донька:

• н becomes soft because of ь

A rough pronunciation guide:

• донька ≈ DON'ka, with a softened n

The soft sign is very important in Ukrainian because it can affect pronunciation and sometimes meaning.

Yes. Both донька and дочка mean daughter.

However:

• донька is very common and often feels more natural in modern everyday Ukrainian
• дочка also exists and is correct

A learner will most often encounter донька, so it is a very good word to know well.