De arts zegt dat de wond schoon moet blijven en dat het verband morgen vervangen moet worden.

After a verb like zeggen (to say), Dutch normally introduces the reported statement with dat. It works like English that in The doctor says that....

One important difference from English: Dutch usually keeps dat, while English often leaves that out. So Dutch strongly prefers De arts zegt dat..., not just De arts zegt... followed immediately by the clause.

Because the sentence contains two coordinated subordinate clauses:

• dat de wond schoon moet blijven
• dat het verband morgen vervangen moet worden

Repeating dat is very natural and helps make the structure clear. In English, you might say that ... and that ... or sometimes omit the second that. In Dutch, repeating dat is especially common, and here it sounds better because the second clause has a different subject: de wond vs het verband.

This is the difference between a main clause and a subordinate clause.

In the main clause, Dutch usually follows the verb-second rule:

• De arts zegt ...

The finite verb zegt is in second position.

After dat, you get a subordinate clause, and in subordinate clauses the finite verb usually moves toward the end:

• dat de wond schoon moet blijven
• dat het verband morgen vervangen moet worden

So the unusual-looking word order is caused by dat.

This is a modal construction:

• moet = must / has to
• blijven = stay / remain

Together, moet blijven means must stay or must remain.

Dutch modals work a lot like English ones:
must stay, can go, will come
=
moet blijven, kan gaan, zal komen

Because Dutch modal verbs take a bare infinitive, just like English.

So you say:

• moet blijven
• moet worden
• kan komen

not:

• moet te blijven
• moet te worden

This is similar to English must stay, not must to stay.

Because schoon is the predicate adjective that goes with blijven: to stay clean.

So:

• de wond blijft schoon = the wound stays clean
• de wond schoon moet blijven = the wound must stay clean

In the subordinate clause, the adjective stays before the final verb cluster. That is why schoon comes before moet blijven.

Because this part is a passive construction with a modal.

• moet = must / has to
• worden = be, used to form the passive
• vervangen = replaced

So vervangen moet worden means must be replaced.

You can think of it like this:

• active: Iemand moet het verband vervangen = Someone must replace the bandage
• passive: Het verband moet vervangen worden = The bandage must be replaced

In the subordinate clause, the verbs collect at the end.

Here it functions as the past participle in the passive construction, even though it looks identical to the infinitive.

That happens with many Dutch verbs that have an inseparable prefix, such as vervangen. Their past participle often has the same form as the infinitive.

Compare:

• infinitive: Ik wil het verband vervangen = I want to replace the bandage
• participle in passive: Het verband moet vervangen worden = The bandage must be replaced

So the form is the same, but the grammar is different.

Because worden forms the normal action passive: it focuses on the action of being replaced.

• Het verband moet vervangen worden = The bandage must be replaced

By contrast, zijn usually describes the resulting state:

• Het verband is vervangen = The bandage has been replaced / is replaced

Here the doctor is talking about what needs to happen, so worden is the right choice.

In Dutch subordinate clauses, adverbs like morgen often appear in the middle part of the clause, before the final verb group.

So:

• dat het verband morgen vervangen moet worden

is the normal order.

In a main clause, you might see:

• Het verband moet morgen vervangen worden

The time word is still before the infinitive/passive part.

Yes, you may also hear dat het verband morgen moet worden vervangen. That word order is also possible.

Dutch verb clusters allow some variation, especially in longer combinations like modal + passive. The version in your sentence, vervangen moet worden, is completely normal and idiomatic.

So both are possible, but the exact preference can vary by style and region.

Because Dutch nouns have grammatical gender for article choice:

• de arts
• de wond
• het verband

Arts and wond are de-words.
Verband is a het-word.

Unfortunately, this often has to be learned noun by noun. There are some patterns, but for many everyday nouns the safest approach is to memorize the article together with the noun.

Because the important thing here is the medical instruction, not the person doing the action.

Dutch, like English, often uses the passive when the agent is unknown, obvious, or unimportant:

• het verband moet vervangen worden = the bandage must be replaced

This sounds more natural in instructions than explicitly naming someone. If needed, Dutch could use an active version, such as:

• ... dat iemand morgen het verband moet vervangen
• ... dat de verpleegkundige morgen het verband moet vervangen

But the passive is the most neutral and typical wording here.