Ja čitam knjigu svako veče.

Yes. In Serbian, the verb ending in čitam already tells you the subject is I.

• čitam = I read / I am reading

So ja is often optional. You can say just:

• Čitam knjigu svako veče.

Adding ja can make the subject clearer or more emphatic, like:

• I read a book every evening.
• As for me, I read a book every evening.

So in this sentence, ja is not required, but it is perfectly correct.

Čitam is the 1st person singular present tense form of the verb čitati, meaning to read.

So:

• čitati = to read
• čitam = I read / I am reading

Serbian present tense often covers both English meanings:

• I read
• I am reading

The exact meaning depends on context. In this sentence, because of svako veče, it is understood as a habitual action: I read every evening.

Because knjigu is in the accusative case, which is used for the direct object of the verb.

• knjiga = book (dictionary form, nominative)
• knjigu = book (accusative singular)

Since the sentence answers What do I read?, Serbian uses the accusative:

• Ja čitam knjigu. = I am reading a book / I read a book.

This is very common with feminine nouns ending in -a:

• nominative: žena

• accusative: ženu

• nominative: kuća
• accusative: kuću

So knjiga → knjigu follows a regular pattern.

It can mean either, depending on context.

Serbian does not have articles like English a and the, so knjigu by itself does not show that distinction.

So this sentence could mean:

• I read a book every evening
• I read the book every evening

In real use, context tells you which one is meant. Very often, without extra context, English speakers translate it naturally as I read a book every evening.

Svako veče means every evening.

It is made of:

• svako = every
• veče = evening

Veče is a neuter noun, and svako agrees with it in gender, number, and case.

This expression is commonly used to show repeated time:

• svako jutro = every morning
• svaki dan = every day
• svake nedelje = every week

In this sentence, svako veče tells us that the action happens regularly, not just once.

Both can be correct, but they are slightly different ways of expressing every evening.

• svako veče = every evening
• svake večeri = every evening / each evening

Both are natural. Svako veče is very common and straightforward in everyday speech.
Svake večeri is also common and can sound a bit more literary or stylistically different depending on context.

So:

• Ja čitam knjigu svako veče.
• Ja čitam knjigu svake večeri.

Both are acceptable and natural.

Here it describes a habit.

The clue is svako veče = every evening. That tells us the action is repeated regularly.

So the sentence means something like:

• I read a book every evening.
• I am in the habit of reading every evening.

Without a time expression, Ja čitam knjigu could also mean I am reading a book right now. But with svako veče, the habitual meaning is the natural one.

Čitati is an imperfective verb.

In Serbian, aspect is very important:

• imperfective verbs describe ongoing, repeated, habitual, or general actions
• perfective verbs describe completed actions

Because this sentence talks about a repeated habit (every evening), the imperfective čitati is the right choice.

Its common perfective partner is pročitati, which means something like to read through / to finish reading.

Compare:

• Čitam knjigu svako veče. = I read a book every evening.
• Pročitam knjigu za dva dana. = I finish reading a book in two days.

So the aspect matches the meaning very well here.

Yes. Serbian word order is more flexible than English word order because case endings help show the role of each word.

The neutral order here is:

• Ja čitam knjigu svako veče.

But you could also say:

• Svako veče čitam knjigu.
• Knjigu čitam svako veče.

These versions are still grammatical, but the emphasis changes:

• Svako veče čitam knjigu. emphasizes every evening
• Knjigu čitam svako veče. emphasizes the book

So the original sentence is a normal, neutral way to say it, but other orders are possible.

The letter č is pronounced roughly like ch in church, but usually with a firmer, clearer sound.

So:

• čitam sounds roughly like CHEE-tam
• veče sounds roughly like VEH-cheh

A few pronunciation notes:

• č is always pronounced the same way
• Serbian spelling is very regular, so words are usually pronounced as written
• e is usually like e in met, not like English ee

Also, English speakers often confuse č and ć. In many learning stages, the difference is subtle, but it is a real distinction in Serbian.

Because Serbian often expresses time without a preposition where English uses one.

English says:

• in the evening
• every evening

Serbian can simply say:

• uveče = in the evening
• svako veče = every evening

So you do not need a separate word corresponding to English in here. Serbian time expressions often work differently from English ones.

Grammatically, yes, it could. But in normal interpretation, most people would understand it more generally as a habitual action: I read a book every evening.

Because Serbian has no articles, knjigu could refer to:

• a book
• the book
• sometimes even books in a general activity sense, depending on context

If you wanted to make it clearer that it is the same specific book, context or extra wording would help, for example:

• Ja čitam tu knjigu svako veče. = I read that book every evening.
• Ja svako veče čitam istu knjigu. = Every evening I read the same book.

So the original sentence is slightly open, and context decides the most natural interpretation.