Kalau tiket pulang-pergi itu sudah dibeli, kita tidak perlu antre di loket lagi.

Kalau usually means if in sentences like this.

So:

• Kalau tiket pulang-pergi itu sudah dibeli... = If the round-trip ticket has already been bought...

In everyday Indonesian, kalau is very common and natural in conversation. Depending on context, it can sometimes feel a bit like when, but here the most natural reading is if.

Compare:

• kalau = common, everyday if
• jika = more formal if
• bila = also if, somewhat formal/literary

So this sentence sounds normal and conversational.

Tiket pulang-pergi means a round-trip ticket or return ticket.

Breakdown:

• tiket = ticket
• pulang = go home / return
• pergi = go / leave
• pulang-pergi = round trip, return journey

The hyphen shows a fixed paired expression. Indonesian often uses hyphens in repeated or paired forms like this.

So:

• tiket pulang-pergi = return ticket / round-trip ticket

You may also see this kind of meaning expressed in other ways, but pulang-pergi is very standard.

Here itu works like a determiner, similar to that or sometimes the in English.

So:

• tiket pulang-pergi itu can mean that round-trip ticket or the round-trip ticket we’re talking about

In Indonesian, itu after a noun often points to something already known in the conversation, not always something physically far away.

Compare:

• tiket pulang-pergi = a round-trip ticket / round-trip ticket
• tiket pulang-pergi itu = that/the round-trip ticket

So in this sentence, itu helps make the ticket sound specific and already identifiable.

Sudah means already, and it often marks that something has been completed.

So:

• sudah dibeli = has already been bought / is already bought

It tells you the buying is finished.

Compare:

• dibeli = bought / is bought
• sudah dibeli = already bought / has been bought already

In everyday Indonesian, sudah is extremely common for expressing completed actions.

Because this sentence uses the passive form.

• membeli = to buy / buy, active
• dibeli = bought / to be bought, passive

In tiket pulang-pergi itu sudah dibeli, the focus is on the ticket, not on the person who bought it.

Literally, it is closer to:

• that round-trip ticket has already been bought

rather than:

• someone has already bought that round-trip ticket

This is very common in Indonesian. If the thing affected by the action is more important than the doer, Indonesian often uses the passive.

The sentence does not explicitly say who bought it because Indonesian often leaves the agent unstated when it is obvious, unimportant, or general.

So:

• sudah dibeli = has already been bought

The speaker may assume the listener can infer who did it, or the exact person may not matter.

If you wanted to add the doer, you could say something like:

• sudah dibeli oleh kita = has already been bought by us
• sudah saya beli = I have already bought it

But in the original sentence, the important point is simply that the ticket is already taken care of.

This is an important distinction in Indonesian:

• kita = we, including the listener
• kami = we, excluding the listener

So kita tidak perlu antre... means:

• we don’t need to queue... with the listener included in that we

That makes sense if the speaker and listener are both part of the trip or both affected by the situation.

If the speaker meant we but not you, then kami would be used instead.

Yes, basically.

• tidak = not
• perlu = necessary / need to

So:

• tidak perlu antre = do not need to queue

In Indonesian, perlu is commonly used in this pattern:

• perlu + verb
• tidak perlu + verb

Examples:

• Saya perlu pergi. = I need to go.
• Kita tidak perlu menunggu. = We do not need to wait.

So in your sentence:

• kita tidak perlu antre di loket lagi = we don’t need to line up at the counter anymore

Good question. In modern Indonesian, antre is often used directly as a verb in everyday language.

So:

• antre = queue / line up / wait in line

You may also encounter forms like:

• mengantre
• berantre

But the bare form antre is very common, especially in speech and informal-to-neutral writing.

After perlu, a bare verb is also very natural:

• tidak perlu antre
• tidak perlu menunggu
• tidak perlu bayar

So tidak perlu antre sounds perfectly normal.

Di loket means at the counter, at the ticket window, or at the booth, depending on context.

Breakdown:

• di = at / in / on
• loket = counter, booth, ticket window, service window

A loket is the place where tickets or services are handled, such as at a station, terminal, or office.

So antre di loket means:

• queue at the ticket counter
• line up at the service window

Here lagi means anymore, not literally again.

So:

• tidak perlu antre di loket lagi = don’t need to queue at the counter anymore

This is a very common pattern:

• tidak ... lagi = no longer / not anymore

Examples:

• Saya tidak tinggal di sana lagi. = I don’t live there anymore.
• Mereka tidak bekerja di situ lagi. = They don’t work there anymore.

So in your sentence, lagi shows that queuing at the counter used to be necessary, but now it is not.

The kalau clause does not have to come first. Indonesian allows either order.

Original:

• Kalau tiket pulang-pergi itu sudah dibeli, kita tidak perlu antre di loket lagi.

Also possible:

• Kita tidak perlu antre di loket lagi kalau tiket pulang-pergi itu sudah dibeli.

Both are grammatical.

Putting the kalau clause first often makes the condition clearer right away, much like English:

• If X, then Y

So the original order is very natural.

The comma is helpful and standard in writing, but it is mainly a punctuation choice rather than a special grammar rule that changes the meaning.

With the comma:

• Kalau tiket pulang-pergi itu sudah dibeli, kita tidak perlu antre di loket lagi.

It clearly separates:

1. the condition
2. the main statement

In casual writing, people may sometimes omit punctuation, but the comma is a good choice here.

Yes. Both are valid ways to understand it, depending on how literal you want to be.

• sudah dibeli literally points to a completed passive action: has been bought
• In natural English, you might also say: already bought

So these can all work:

• If that round-trip ticket has already been bought, we don’t need to queue at the counter anymore.
• If the round-trip ticket is already bought, we don’t need to queue at the counter anymore.
• If the round-trip ticket has already been purchased, we don’t need to line up at the counter anymore.

The Indonesian itself is passive and completion-focused.