Kód lze rozluštit.

Lze means something like it is possible to or can be.

So Kód lze rozluštit literally works like:

The code — it is possible to decipher.

In natural English, that becomes The code can be deciphered.

A useful thing to remember is that lze is an impersonal form. It does not mean he/she can or I can. It is used for general possibility.

Because the pattern here is:

lze + infinitive

So Czech is saying it is possible to decipher the code, not using a normal finite verb like deciphers or will decipher.

This is a very common structure in more formal Czech:

• To lze udělat. = That can be done.
• Problém lze vyřešit. = The problem can be solved.

So rozluštit stays in the infinitive because it is part of that construction.

Here kód is best understood as the direct object of rozluštit, so it is in the accusative.

Why does it look like nominative? Because for a masculine inanimate singular noun, nominative and accusative often have the same form.

So:

• nominative: kód
• accusative: kód

You can see this more clearly with a noun whose forms differ:

• Zpráva = message/report
• Zprávu lze rozluštit. = The message can be deciphered.

There, zprávu clearly shows the accusative.

Because Czech often uses an impersonal construction where English prefers a passive.

Czech structure:

• Kód lze rozluštit.
• literally: It is possible to decipher the code.

Natural English:

• The code can be deciphered.

So the Czech sentence is not a classic passive in form, but it often corresponds to a passive translation in English.

Rozluštit is perfective, while luštit is imperfective.

Here, the perfective verb is natural because the sentence is about reaching a result:

• to decipher successfully
• to solve / crack

So Kód lze rozluštit means the code can be deciphered all the way to completion.

If you used luštit, it would focus more on the process of working on it, not necessarily finishing it. In this sentence, rozluštit is the more natural choice.

Yes, Kód lze rozluštit sounds somewhat formal, neutral-written, or concise.

In everyday speech, people often use other patterns, such as:

• Kód se dá rozluštit.
• Ten kód jde rozluštit.
• Je možné kód rozluštit.

All of these can express a similar idea, though the tone is a little different.

So if you see lze + infinitive, it is good to recognize it as perfectly normal Czech, but somewhat more formal than casual conversation.

Yes. You could also say:

Kód může být rozluštěn.

That means The code can be deciphered too.

But this version is often felt to be even more formal or bookish than Kód lze rozluštit.

So:

• Kód lze rozluštit = formal, efficient, very common in writing
• Kód může být rozluštěn = more explicitly passive, often more formal

Because Czech has no articles.

So kód can mean:

• a code
• the code
• sometimes even code in a broader sense

The exact meaning depends on context.

In a sentence like Kód lze rozluštit, English usually chooses the code or a code, depending on the situation. Czech leaves that unstated unless something else in the context makes it clear.

Because Czech does not need a dummy subject like English it.

English says:

• It is possible to decipher the code.

Czech can simply say:

• Lze rozluštit kód.
• or Kód lze rozluštit.

So Czech often leaves out the kind of grammatical placeholder that English requires.

Yes. Czech word order is flexible, though not random.

You could also say:

• Lze rozluštit kód.

That is grammatically fine. The difference is mainly in information structure:

• Kód lze rozluštit.
  The code is the topic; then you say something about it.

• Lze rozluštit kód.
  This sounds a little more like presenting the possibility itself first.

In many contexts, Kód lze rozluštit is the more natural order if you are already talking about the code.

You simply negate lze:

Kód nelze rozluštit.

That means:

• The code cannot be deciphered.
• It is not possible to decipher the code.

This is a very useful pattern:

• To nelze udělat. = That cannot be done.
• Problém nelze vyřešit. = The problem cannot be solved.

A rough guide:

• Kód → long ó; final d is pronounced like t at the end, so roughly koht
• lze → one syllable, roughly lz-eh; the lz cluster may feel awkward at first
• rozluštit → stress on the first syllable: ROZ-lu-shtit

A rough English-style approximation would be:

koht lzeh ROZ-loo-shtit

A few pronunciation points:

• Czech stress is almost always on the first syllable
• š sounds like sh
• final voiced consonants are often devoiced, which is why kód sounds more like it ends in t

Often yes, but not mechanically.

In many sentences, lze corresponds well to English can or can be:

• To lze udělat. = That can be done.

But grammatically, lze is not working exactly like an ordinary personal modal verb such as můžu / můžeš / může. It is an impersonal possibility construction.

So for learning purposes, a good shortcut is:

• lze + infinitive = it is possible to ... / can be ...

That will usually give you the right meaning and help you understand the structure.