Stroj mora isprati rublje.

• stroj = machine
• mora = must / has to
• isprati = to rinse out / to wash out completely
• rublje = laundry / clothes / linen

So the structure is basically:

machine + must + rinse/wash out + laundry

Stroj is in the nominative singular because it is the subject of the sentence — the thing doing the action.

Its basic dictionary form is also stroj, so nothing has changed here.

Mora is the 3rd person singular form of morati, which means must or to have to.

Because the subject is stroj (machine), Croatian uses mora:

• ja moram = I must
• ti moraš = you must
• on/ona/ono mora = he/she/it must

Since stroj is grammatically treated like it, mora is the correct form.

After morati, Croatian normally uses an infinitive:

• moram raditi = I must work
• mora doći = he/she/it must come
• stroj mora isprati rublje = the machine must rinse the laundry

So this is a very common pattern:

subject + morati + infinitive

This is about aspect, which is very important in Croatian verbs.

• isprati = perfective → to rinse/wash out completely, as a finished action
• ispirati = imperfective → to be rinsing, to rinse repeatedly, or to talk about the process in a more general way

With mora, Croatian often uses the perfective infinitive when the idea is that the action must be completed.

So mora isprati suggests: the machine has to finish rinsing the laundry / must rinse it out completely

Rublje is the direct object, so it is in the accusative case.

In this noun, the nominative and accusative forms look the same:

• nominative: rublje
• accusative: rublje

That is why you do not see a visible ending change here.

In Croatian, rublje is a collective noun. It is grammatically singular, even though it refers to a group of items like clothes or laundry.

This is similar to how English can use laundry as a mass noun rather than counting individual pieces.

So Croatian says:

• rublje je mokro = the laundry is wet

not a plural form meaning the laundries in this context.

It can mean different but related things depending on context:

• laundry
• washing
• linen
• sometimes underwear or clothes, depending on the situation

In a sentence with a machine washing or rinsing it, laundry is usually the most natural meaning.

These verbs are related but not identical:

• oprati = to wash
• isprati = to rinse out / wash out / rinse thoroughly

So if the focus is on the full washing of clothes, oprati may be used. If the focus is specifically on the rinsing stage, isprati is better.

A washing machine can do both, but this sentence specifically uses the idea of rinsing out.

Yes. Croatian word order is more flexible than English because cases help show what each word is doing.

The neutral order here is:

Stroj mora isprati rublje.

But other orders are possible for emphasis, for example:

• Rublje mora isprati stroj. = It is the machine that must rinse the laundry.
• Stroj rublje mora isprati. = stronger focus on isprati

Even though the order can change, the original version sounds natural and neutral.

Croatian does not have articles like the or a/an.

So stroj can mean:

• a machine
• the machine

and rublje can mean:

• laundry
• the laundry

The exact meaning depends on context.

A simple English-friendly approximation is:

stroy MO-ra ees-pra-ti ROO-blyeh

A few notes:

• stroj rhymes roughly with English toy, but starts with str-
• mora = MO-ra
• isprati has the stress usually on the first syllable: IS-prati
• rublje can be tricky; the lj is a soft sound, a bit like lli in some pronunciations of million, though not exactly the same

Yes, but the meaning changes slightly.

• mora = must / has to → stronger necessity
• treba = should / needs to / is supposed to → often softer, depending on context

So:

• Stroj mora isprati rublje. = The machine must rinse the laundry.
• Stroj treba isprati rublje. = The machine should rinse the laundry / needs to rinse the laundry.

In many contexts both are possible, but mora is stronger.