Smlouva na dobu neurčitou nemá závazek.

Literally, na dobu neurčitou means for an indefinite period.

This is a very common fixed phrase in Czech, especially with contracts and employment:

• smlouva na dobu neurčitou = an open-ended / indefinite-term contract
• pracovní poměr na dobu neurčitou = permanent employment

The opposite is na dobu určitou, meaning for a fixed period.

Because the phrase uses the accusative case.

The dictionary forms are:

• doba = period, term
• neurčitý = indefinite

After na in this expression, Czech uses the accusative:

• doba → dobu
• neurčitá → neurčitou

So:

• na dobu neurčitou

The adjective has to agree with the noun in:

• gender: feminine
• number: singular
• case: accusative

That is why the ending is -ou.

Because the subject is smlouva, which is singular.

The verb is from mít = to have:

• má = he/she/it has
• nemá = he/she/it does not have

Here, smlouva is the subject, so Czech uses nemá:

• Smlouva ... nemá ...

Even though smlouva is feminine, the present-tense verb form does not change for gender, only for person and number.

In this sentence, závazek is the direct object, so it is in the accusative singular.

Its dictionary form is also závazek. For many masculine inanimate nouns in Czech, the nominative and accusative singular look the same. So:

• nominative: závazek
• accusative: závazek

That is why it does not visibly change here.

A learner may also notice that Czech sometimes uses the genitive after negation, but in modern standard Czech, with a sentence like this, the accusative závazek is the normal and expected choice.

Because Czech does not have articles.

So smlouva can mean:

• a contract
• the contract

Which one is meant depends on context.

This is very normal in Czech, and learners usually have to get used to reading definiteness from the situation instead of from a separate word.

It is grammatically understandable, but it may sound a little unusual depending on the intended meaning.

Why? Because závazek usually means something like:

• obligation
• commitment
• liability

A native speaker might find smlouva ... nemá závazek slightly odd, because a contract usually creates obligations rather than having no obligation.

If the intended meaning is that the contract has no fixed end date, more natural Czech would often be something like:

• Smlouva na dobu neurčitou nemá stanovené datum ukončení.
• Smlouva na dobu neurčitou není časově omezená.

So the sentence is useful for grammar study, but in real-life Czech, the best wording depends on what exact meaning is intended.

Czech word order is fairly flexible, but not every rearrangement sounds equally natural.

The neutral order here is:

• Smlouva na dobu neurčitou nemá závazek.

That keeps smlouva na dobu neurčitou together as one clear noun phrase.

If you move words around, the meaning may stay similar, but the emphasis changes, and some versions may sound awkward. For example, splitting na dobu neurčitou away from smlouva is usually not the best choice unless you have a special reason for emphasis.

So for a learner, the safest option is to keep the phrase together.

The opposite is na dobu určitou.

Compare:

• smlouva na dobu neurčitou = open-ended / indefinite-term contract
• smlouva na dobu určitou = fixed-term contract

This pair is extremely common, so it is worth learning as a set.

Yes. Czech very often says pracovní smlouva when the context is employment.

• smlouva = contract / agreement in general
• pracovní smlouva = employment contract

So if the context is a job, a native speaker might more naturally say:

• Pracovní smlouva na dobu neurčitou ...

But if the context already makes it clear that we are talking about employment, simply smlouva can still be fine.