Menjač radi dobro.

Menjač is a noun. In everyday Serbian, it most often means gearbox or transmission, and sometimes it can also refer to a gear shifter/gear lever, depending on context.

In Menjač radi dobro, it is most naturally understood as the subject of the sentence: the gearbox/transmission is functioning well.

Grammatically, menjač is:

• masculine
• singular
• in the nominative case here, because it is the subject

Radi is the 3rd person singular present tense of raditi.

The verb raditi can mean:

• to work
• to function
• to operate

So in this sentence, radi means something like works / is working / functions.

A few present-tense forms of raditi are:

• ja radim = I work
• ti radiš = you work
• on/ona/ono radi = he/she/it works

Since menjač is singular, Serbian uses radi.

Because dobro is being used as an adverb, not as an adjective.

• dobar = good (masculine adjective)
• dobra = good (feminine adjective)
• dobro = good (neuter adjective) or well (adverb)

In Menjač radi dobro, dobro means well, and it modifies the verb radi.

So:

• dobar menjač = a good gearbox
• menjač radi dobro = the gearbox works well

This is a very common pattern in Serbian:

• Auto ide dobro = The car runs well
• On peva dobro = He sings well

Serbian does not have articles like a/an/the.

So menjač can mean:

• a gearbox
• the gearbox

The exact meaning depends on context.

That is why Menjač radi dobro can be understood as:

• The gearbox works well or
• A gearbox works well

In real life, context usually makes it clear which one is meant.

The most neutral word order here is:

Menjač radi dobro.
subject + verb + adverb

This is the most straightforward way to say it.

Serbian word order is fairly flexible, though. You may also hear different orders for emphasis, for example:

• Dobro radi menjač.
• Radi dobro menjač.

These are less neutral and may sound more marked or stylistic, depending on context.

For learners, Menjač radi dobro is the safest basic order.

It can be either, depending on context.

Serbian present tense often covers both:

• works
• is working

So Menjač radi dobro could mean:

• The gearbox works well
• The gearbox is working well

English often chooses between simple present and present progressive more strictly than Serbian does.

A useful approximate pronunciation is:

MEN-yach

A few details:

• nj sounds like the ny in canyon
• č sounds like ch in church, but a bit firmer

So menjač is roughly:

• me-nyač

If it helps, the Cyrillic spelling is:

Мењач

A rough guide is:

MEN-yach RA-dee DO-broh

More specifically:

• menjač = MEN-yach
• radi = RA-dee
• dobro = DO-broh

Cyrillic: Мењач ради добро.

It is in the nominative case.

That is because menjač is the subject of the sentence, the thing that is doing the action of radi.

So:

• menjač = nominative singular
• it answers the question What works well?
• answer: menjač

Yes. Dobro can be either:

1. the neuter singular form of the adjective good
2. an adverb meaning well

Here it is an adverb.

Compare:

• Ovo je dobro. = This is good.
  Here dobro is an adjective, agreeing with a neuter subject.

• Menjač radi dobro. = The gearbox works well.
  Here dobro is an adverb, modifying the verb.

This dual use is very common in Serbian.

Yes. Menjač dobro radi is also correct and very natural.

Both are possible:

• Menjač radi dobro
• Menjač dobro radi

The difference is small. Serbian allows adverbs to move around more freely than English.

As a beginner, you can treat both as acceptable, though Menjač radi dobro is a very clear basic model.

Yes, it does. It sounds natural if someone is commenting on how the transmission/gearbox is functioning.

Depending on the situation, native speakers might also say:

• Menjač je dobar. = The gearbox is good.
• Menjač dobro funkcioniše. = The gearbox functions well.
• Menjač šalta dobro. = The gearbox shifts well.

But Menjač radi dobro is perfectly normal and understandable.

Very often, yes, but context matters.

Menjač commonly refers to:

• the gearbox
• the transmission
• sometimes the shifter/gear lever

In automotive contexts, the intended meaning is usually clear from the conversation.

So if you see Menjač radi dobro in a car-related context, the transmission/gearbox works well is the most likely interpretation.