Kad bi bilo više vremena, ponovili bismo zadatak još jednom.

In this sentence, kad bi is used like if in a hypothetical situation.

So:

• Kad bi bilo više vremena = If there were more time

Although kad often means when, with bi it commonly introduces an unreal or imagined condition. In English, this is similar to:

• If there were...
• If we had...

In everyday Croatian, kad bi and ako bi can both introduce conditional clauses, but kad bi is very common in this kind of hypothetical statement.

Bilo is the past participle of biti (to be) in the neuter singular form.

Here it appears in the conditional structure:

• bi bilo = would be / were

Croatian often forms this kind of hypothetical clause with bi + past participle.

Why neuter singular? Because Croatian often uses neuter singular bilo in impersonal expressions like:

• bilo je vremena = there was time
• kad bi bilo više vremena = if there were more time

So this is not agreeing with a visible noun in the way an adjective might; it is part of an impersonal there is/there was type construction.

Because after više in this meaning (more), Croatian normally uses the genitive.

So:

• vrijeme = nominative singular, time
• vremena = genitive singular

That is why you get:

• više vremena = more time

This is very common in Croatian:

• više novca = more money
• više vode = more water
• više ljudi = more people

So više often triggers the genitive.

Ponovili bismo means we would repeat.

It is the Croatian conditional form:

• ponovili = past participle, masculine plural form
• bismo = conditional auxiliary for we

Together:

• ponovili bismo = we would repeat

It is written as two words because Croatian builds the conditional analytically, using a participle plus the auxiliary bih, bi, bismo, biste, bi.

Examples:

• ja bih ponovio / ponovila = I would repeat
• mi bismo ponovili = we would repeat

Croatian word order is flexible, so you can also hear:

• bismo ponovili

But in standard style, the auxiliary often appears in the second position of its clause, which helps explain the placement here.

Because ponoviti is the perfective verb, meaning to repeat something once / to do it again as a completed action.

Here the sentence means:

• we would repeat the task one more time

That suggests a single completed repetition, so ponoviti is a natural choice.

Compare:

• ponoviti = to repeat once, to redo, to say/do again as a completed action
• ponavljati = to repeat repeatedly, to be repeating, to keep repeating

So:

• ponovili bismo zadatak još jednom = we would repeat the task one more time
• ponavljali bismo zadatak would suggest repeated or habitual repetition, depending on context

Because it agrees with the implied subject we (mi).

In Croatian, past participles used in the conditional agree with the subject in gender and number.

Here, ponovili is:

• plural
• traditionally the masculine plural form

This form is commonly used for:

• a group of men
• a mixed-gender group
• sometimes a general we

If the speakers were all female, you could say:

• ponovile bismo

So the sentence as given assumes either a mixed group, a masculine group, or a generic default plural.

Because Croatian usually drops subject pronouns when they are already clear from the verb form.

Here, bismo tells you the subject is we.

So:

• ponovili bismo already means we would repeat

Adding mi is possible, but usually only for emphasis or contrast:

• Mi bismo ponovili zadatak još jednom. = We would repeat the task one more time.

That might imply contrast, like we would, but someone else wouldn’t.

Još jednom means once more, one more time, or again.

Literally:

• još = still / more / yet
• jednom = once / one time

Together:

• još jednom = one more time

In this sentence:

• ponovili bismo zadatak još jednom = we would repeat the task one more time

It is a very common phrase in Croatian.

Here jednom is an adverbial form meaning once or one time.

You will often see number words in forms like this when expressing how many times something happens:

• jednom = once
• dvaput / dva puta = twice
• triput / tri puta = three times

With još, it becomes:

• još jednom = once more

So you do not need to think of jednom here as simply the basic numeral one; it is functioning as part of a time-frequency expression.

That version sounds unnatural in standard Croatian.

The auxiliary bismo usually follows the clitic-placement rules, meaning it tends to come early in the clause, often in the second position. In this sentence, the natural options are:

• ponovili bismo zadatak još jednom
• sometimes also zadatak bismo ponovili još jednom, depending on emphasis

But simply starting the main clause with bismo after the comma is usually not the normal neutral word order here.

So the original sentence is the best standard phrasing.

It is an unreal or hypothetical condition.

The meaning is:

• there is not enough time now, or we are imagining a situation with more time

That is why Croatian uses conditional forms in both parts:

• Kad bi bilo više vremena = If there were more time
• ponovili bismo zadatak još jednom = we would repeat the task one more time

This is similar to English second conditional:

• If there were more time, we would repeat the task once more.

Yes, in many contexts it can.

You could say:

• Ako bi bilo više vremena, ponovili bismo zadatak još jednom.

This is understandable and grammatical. However, kad bi is especially common in hypothetical statements like this, and many speakers find it very natural.

Very roughly:

• ako often feels more like plain if
• kad bi is very common for imagined, counterfactual, or wistful situations

But in practice, there is overlap.

Because it is the direct object of ponoviti.

The verb ponoviti takes an object answering what?

• ponoviti što? = repeat what?
• zadatak = the task

Since zadatak is a masculine inanimate noun, its accusative singular is the same as its nominative singular:

• nominative: zadatak
• accusative: zadatak

So the form does not change visibly, but grammatically it is accusative here.

Not really in its current form.

Because of kad bi bilo, the sentence clearly expresses a hypothetical or unreal condition:

• if there were more time
• if there would be more time in a more literal sense, though that is less natural English

If you wanted a more real/open condition such as if there is more time, Croatian would normally use a present-tense structure instead, for example:

• Ako bude više vremena, ponovit ćemo zadatak još jednom.
• Ako ima više vremena... depending on context

So kad bi bilo points strongly to a hypothetical situation, not a straightforward real possibility.