Die kodewoord is so moeilik dat niemand dit raai nie.

Die is the definite article in Afrikaans, so here it means the.

So die kodewoord = the codeword.

A useful thing to remember is that Afrikaans uses die for:

• singular definite nouns: die boek = the book
• plural definite nouns: die boeke = the books

So unlike English, the form does not change.

Afrikaans very often writes compound nouns as a single word.

So:

• kode = code
• woord = word

Together they form kodewoord = codeword

This is very normal in Afrikaans. English sometimes also does this, but Afrikaans does it much more consistently. You will see the same pattern in many nouns.

So ... dat means so ... that.

In this sentence:

• so moeilik = so difficult
• dat = that

So the pattern is:

X is so + adjective + dat + result

Here: Die kodewoord is so moeilik dat niemand dit raai nie.
= The codeword is so difficult that nobody guesses it / that nobody can guess it.

This is a very common structure in Afrikaans.

Because after the verb is, the adjective stays in its basic form.

So:

• Die kodewoord is moeilik = The codeword is difficult

Afrikaans adjectives usually only change form when they come directly before a noun, and even then there are rules about when they take -e. But after a linking verb like is, you normally use the plain form:

• Die vraag is moeilik
• Die toets is maklik

So moeilik here is exactly what you should expect.

Because the part after dat is a subordinate clause, and in Afrikaans the verb often moves toward the end in subordinate clauses.

Main clause:

• Die kodewoord is so moeilik ...

Subordinate clause:

• ... dat niemand dit raai nie

This is a very important word-order pattern in Afrikaans:

• after dat
• after omdat
• after as
• after some other subordinating conjunctions

you often find the verb later in the clause, often at or near the end.

So niemand dit raai nie is normal Afrikaans word order.

Yes, kodewoord already introduced the thing being talked about, but Afrikaans still uses dit here as the object pronoun, meaning it.

So:

• niemand = nobody
• dit = it
• raai = guesses

Together: niemand dit raai nie = nobody guesses it

This works just like English, where you would also normally say nobody guesses it, not just nobody guesses if you want to state the object clearly.

That is a very common question.

Afrikaans often does use a two-part negative, for example:

• Hy raai dit nie. = He does not guess it.

But with negative words like:

• niemand = nobody
• niks = nothing
• geen = no / not any
• nêrens = nowhere

you usually do not add an earlier nie as well. You only keep the final nie.

So:

• Niemand raai dit nie. = Nobody guesses it.
• not Niemand nie raai dit nie

That is why the sentence ends with just the final nie.

Niemand means nobody or no one.

In this sentence:

• niemand dit raai nie = nobody guesses it

It is already negative in meaning, which is why the sentence structure is different from a simple not sentence.

Compare:

• Iemand raai dit. = Someone guesses it.
• Niemand raai dit nie. = Nobody guesses it.

Yes. Raai means to guess.

Examples:

• Kan jy dit raai? = Can you guess it?
• Ek raai die antwoord. = I guess the answer.
• Niemand kan dit raai nie. = Nobody can guess it.

In your sentence, raai is used without kan, but in English we often naturally translate it with can guess because that sounds more idiomatic in context.

So the sentence can be understood as:

• nobody guesses it or more naturally
• nobody can guess it

Afrikaans does not always need to include kan when English would.

The sentence literally says:

• nobody guesses it

But because of the meaning of the whole sentence — so difficult that nobody guesses it — English speakers often understand it as:

• so difficult that nobody can guess it

So the Afrikaans sentence is completely natural without kan. If you added kan, it would make the idea of ability more explicit:

• Die kodewoord is so moeilik dat niemand dit kan raai nie.

That version is also correct.

Possibly in some contexts, but the most direct meaning of kodewoord is codeword.

If you specifically mean a computer or account password, Afrikaans more often uses wagwoord.

So:

• kodewoord = codeword
• wagwoord = password

In a learning sentence like this, kodewoord is best understood as codeword, unless the context clearly shows a password is meant.

A fairly literal breakdown would be:

• Die kodewoord = The codeword
• is = is
• so moeilik = so difficult
• dat = that
• niemand = nobody
• dit = it
• raai = guesses / guess
• nie = negative marker

So, very literally:

The codeword is so difficult that nobody guesses it.

But more natural English might be:

The codeword is so difficult that nobody can guess it.