Ako u retrovizoru vidiš plava svjetla, odmah uspori i provjeri pojas.

Ako means if.

It introduces a condition:

• Ako u retrovizoru vidiš plava svjetla = If you see blue lights in the rear-view mirror

This is a very common pattern in Croatian:

• Ako pada kiša, ostani doma. = If it rains, stay home.
• Ako ga vidiš, nazovi me. = If you see him, call me.

So in your sentence, the first part gives the condition, and the second part tells you what to do if that condition is true.

Because u can mean either in or into, depending on the case.

Here, u retrovizoru means in the rear-view mirror, so it expresses a location, not movement. That is why retrovizor is in the locative case:

• retrovizor = rear-view mirror
• u retrovizoru = in the rear-view mirror

Compare:

• u retrovizoru = in the mirror, inside the visual field of the mirror
• u retrovizor would suggest movement into the mirror, which does not fit here

So u + locative is used because this is a static location.

Retrovizor means rear-view mirror.

In everyday Croatian, it usually refers to the car mirror you look into to see what is behind you. Depending on context, it can mean the interior rear-view mirror or sometimes a side mirror, but here the learner should understand it generally as rear-view mirror.

So:

• u retrovizoru vidiš... = you see ... in the rear-view mirror

Vidiš is the 2nd person singular present tense of vidjeti = to see.

It means you see when speaking to one person informally.

Forms of vidjeti in the present:

• ja vidim = I see
• ti vidiš = you see
• on/ona vidi = he/she sees
• mi vidimo = we see
• vi vidite = you see / you all see / formal you
• oni vide = they see

So the sentence is addressing one person directly and informally:

• Ako ... vidiš ... = If you see ...

If you wanted a polite or plural version, you would say:

• Ako u retrovizoru vidite plava svjetla, odmah usporite i provjerite pojas.

Because Croatian often leaves subject pronouns out when they are already clear from the verb ending.

In English, you usually need you:

• If you see... slow down... check...

In Croatian, the verb endings already show who the subject is:

• vidiš = you see
• uspori = slow down (to one person)
• provjeri = check (to one person)

So adding ti is usually unnecessary unless you want emphasis:

• Ako ti u retrovizoru vidiš plava svjetla... would sound marked or emphatic

Normal Croatian prefers the shorter version without the pronoun.

Because plava svjetla is the correct agreement for blue lights.

Break it down:

• svjetlo = light
• plural: svjetla = lights
• plav = blue
• neuter plural nominative/accusative: plava

Since svjetla is neuter plural, the adjective must match it:

• plava svjetla = blue lights

This can feel surprising to English speakers because the adjective ending -a may look singular, but here it is the normal neuter plural form.

Examples:

• crveno svjetlo = red light
• crvena svjetla = red lights
• plavo svjetlo = blue light
• plava svjetla = blue lights

Because svjetla is a neuter plural noun, and neuter plural adjectives in the nominative and accusative usually end in -a.

So:

• masculine plural: plavi auti
• feminine plural: plave kuće
• neuter plural: plava svjetla

That is why plava svjetla is correct.

Since vidjeti takes a direct object in the accusative, and these are inanimate neuter plural nouns, the accusative form is the same as the nominative here:

• vidiš plava svjetla = you see blue lights

Yes, it literally means lights, and that is natural here.

In driving or road-safety language, plava svjetla refers to the flashing blue lights of police or emergency vehicles. Croatian uses the plural just as English often does:

• blue lights
• flashing lights

So plava svjetla is exactly what you would expect in this kind of context.

Uspori is the imperative form of usporiti, meaning slow down.

So:

• odmah uspori = slow down immediately

This is a command or instruction directed to one person.

It is very common in safety instructions to use the imperative like this:

• stani = stop
• čekaj = wait
• pazi = watch out / be careful
• uspori = slow down

This is a question of aspect.

• usporiti is perfective
• usporavati is imperfective

The imperative uspori from the perfective verb usually tells someone to perform a single, complete action:

• slow down

That fits this context well: you notice blue lights, so you should take action right away.

Usporavaj would sound more like:

• keep slowing down
• be in the process of slowing down
• slow down repeatedly or continuously

In instructions like this, Croatian often prefers the perfective imperative because it focuses on the action being carried out as a complete response.

The same applies to provjeri below.

Provjeri is the imperative singular of provjeriti = to check.

So:

• provjeri pojas = check the seat belt

It is another command addressed to one person informally.

Together, the sentence has two linked imperatives:

• odmah uspori
• i provjeri pojas

= slow down immediately and check the seat belt

Because pojas is the direct object of provjeri, so it is in the accusative case.

For an inanimate masculine noun like pojas, the accusative singular is the same as the nominative singular:

• nominative: pojas
• accusative: pojas

So:

• provjeri pojas = check the belt

Other forms would mean something else:

• pojasom = instrumental, with the belt
• pojasa = genitive, of the belt or used in some other constructions

Here you need the direct object, so pojas is correct.

Yes, in this driving context, pojas naturally means seat belt.

Literally, pojas can mean belt in a broader sense, but in road-safety language it commonly refers to the seat belt. Croatian can also say:

• sigurnosni pojas = safety belt / seat belt

But in context, just pojas is enough.

So the sentence is not talking about a clothing belt; it means the seat belt.

Odmah means immediately / right away.

It is placed before the imperative to modify it directly:

• odmah uspori = slow down immediately

This is the most natural position here, although Croatian word order is fairly flexible. The chosen order sounds very normal and clear in an instruction.

For example:

• Odmah uspori. = Slow down immediately.
• Uspori odmah. = Slow down immediately.

Both are possible, but odmah uspori sounds especially natural in warning-style language.

Because the first part is a conditional clause introduced by ako, and it is followed by the main clause.

So the structure is:

• Ako u retrovizoru vidiš plava svjetla, = conditional clause
• odmah uspori i provjeri pojas. = main clause

This comma is normal in Croatian.

It works like English:

• If you see blue lights in the rear-view mirror, slow down immediately and check your seat belt.

Because the whole sentence is speaking directly to one person informally.

The command forms are:

• uspori = slow down
• provjeri = check

If the instruction were addressed to several people or to one person formally, Croatian would use the plural/formal imperative:

• usporite
• provjerite

So the current sentence is in the informal singular style.

Yes, Croatian word order is more flexible than English, though not every version sounds equally natural.

The original sentence is very natural:

• Ako u retrovizoru vidiš plava svjetla, odmah uspori i provjeri pojas.

Some elements could move, for example:

• Ako vidiš plava svjetla u retrovizoru, odmah uspori i provjeri pojas.

This still sounds natural and means the same thing.

But Croatian still has preferred word orders depending on emphasis and style. The original version is a clear, neutral instruction.

More or less, yes.

In traffic and police contexts, plava svjetla is a very common phrase meaning the blue emergency lights of police or other emergency vehicles.

So even though it is grammatically just blue lights, learners will often encounter it almost like a set traffic-related expression.

Because the sentence combines a condition with instructions.

• vidiš = present tense, describing the possible situation: if you see
• uspori and provjeri = imperatives, telling you what to do in that situation

This pattern is extremely common:

• Ako padne kiša, uđi unutra. = If it rains, go inside.
• Ako ga vidiš, reci mu. = If you see him, tell him.

So the tense and mood change because the sentence has two different functions:

1. describe the condition
2. give the response

It could, but it would change the nuance a little.

• vidiš = you see
• ugledaš = you catch sight of / you spot

Ugledati often emphasizes the moment of noticing something. In a road-safety sentence, ugledaš could sound a bit more dramatic or moment-specific.

The original vidiš is broad, neutral, and very natural.

So:

• Ako u retrovizoru vidiš plava svjetla... = neutral and standard
• Ako u retrovizoru ugledaš plava svjetla... = if you spot blue lights...

Both are possible, but vidiš is simpler and more general.

Not perfectly.

A very literal translation would be something like:

• If in the rear-view mirror you see blue lights, immediately slow down and check the belt.

That is understandable, but natural English would normally say:

• If you see blue lights in your rear-view mirror, slow down immediately and check your seat belt.

Croatian often omits possessives like your when they are obvious from context, and its word order is more flexible. So it is better to understand the grammar rather than translate every word mechanically.