Dersom bostedsadressen endres, sender hun flyttemeldingen.

Yes. Dersom and hvis both mean if.

The difference is mostly one of style:

• hvis is very common in everyday speech and writing
• dersom sounds a bit more formal, official, or written

In a sentence like this, which sounds administrative or official, dersom fits very naturally.

You could also say:

• Hvis bostedsadressen endres, sender hun flyttemeldingen.

That would mean the same thing.

Bostedsadressen is a compound noun, which is extremely common in Norwegian.

It is made up of:

• bosted = place of residence
• adresse = address

Together, bostedsadresse means residential address or address of residence.

Then the ending -n makes it definite:

• en bostedsadresse = a residential address
• bostedsadressen = the residential address

Norwegian often combines words into one noun where English would use two or more separate words.

Because the first part is bosted, and when Norwegian forms compounds, that whole stem is often kept.

So:

• bosted
  • adresse → bostedsadresse

The -s- here is a linking element that often appears in compounds. It does not have a separate meaning by itself, but it helps connect the two parts naturally.

This is very common in Norwegian compound words.

Yes. endres is a passive form.

It comes from the verb å endre = to change.

Here:

• endre = to change something
• endres = is changed / gets changed

So bostedsadressen endres means:

• the residential address is changed
• or the residential address gets changed

This -s passive is very common in Norwegian, especially in formal language, instructions, and official texts.

Compare:

• Hun endrer adressen. = She changes the address.
• Adressen endres. = The address is changed.

Yes, absolutely.

• bostedsadressen endres
• bostedsadressen blir endret

Both can mean the residential address is changed.

The difference is mainly style:

• endres is shorter and often more formal or official
• blir endret can sound a little more explicit and sometimes a bit more natural in less formal contexts

In administrative language, endres is very typical.

This is because Norwegian uses verb-second word order in main clauses.

When the sentence starts with something other than the subject, the finite verb must come before the subject.

Here, the first part is the conditional clause:

• Dersom bostedsadressen endres

After that comes the main clause:

• sender hun flyttemeldingen

So the order is:

1. fronted clause: Dersom bostedsadressen endres
2. verb: sender
3. subject: hun
4. object: flyttemeldingen

If you remove the fronted dersom clause, you get the normal order:

• Hun sender flyttemeldingen.

This inversion after a fronted element is one of the most important word-order patterns in Norwegian.

Flyttemeldingen is also a compound noun:

• flytte = move
• melding = message, notice, notification

Together, flyttemelding means change-of-address notification or moving notification.

With the definite ending:

• en flyttemelding = a change-of-address notification
• flyttemeldingen = the change-of-address notification

In practice, this often refers to the official notice you send when you move.

The definite form suggests a specific, understood notification.

So flyttemeldingen implies something like:

• the change-of-address notification
• the one that is required in this situation
• the standard or expected notification

Official or procedural Norwegian often uses the definite form this way when referring to a known document, form, or step in a process.

If you said en flyttemelding, it would sound less specific:

• sender hun en flyttemelding = she sends a change-of-address notification

That is possible grammatically, but it does not sound quite as tied to a specific official process.

Yes, it can be.

Norwegian often uses the present tense for:

• general rules
• routines
• instructions
• future actions that follow from a condition

So this sentence is not necessarily about something happening right now. It can mean something like:

• If the residential address changes, she submits the change-of-address notification.
• If the residential address is changed, she sends the notification.

This kind of present tense is very common in regulations, instructions, and official descriptions of what happens in a given case.

Yes. The comma separates the conditional clause from the main clause:

• Dersom bostedsadressen endres, sender hun flyttemeldingen.

In standard writing, a clause introduced by dersom or hvis is often followed by a comma when it comes first.

This helps show the structure clearly:

• condition: Dersom bostedsadressen endres
• result/main action: sender hun flyttemeldingen

Grammatically, hun means she, so it normally refers to a female person.

Whether it is a specific person depends on context. In an isolated sentence like this, it most naturally refers to some previously known female person.

In official or instructional language, though, example sentences sometimes use han or hun simply as sample persons.

If the sentence were meant to be fully neutral or general, Norwegian might instead use a noun phrase like:

• personen
• man
• vedkommende

But as written, hun is just she.

Yes. It sounds fairly formal and administrative.

The things that make it sound formal include:

• dersom instead of the more everyday hvis
• the passive endres
• long compound nouns like bostedsadressen and flyttemeldingen
• the overall official, procedural style

In everyday speech, someone might say something simpler, such as:

• Hvis adressen hennes endrer seg, sender hun inn flyttemelding.
• Hvis hun bytter adresse, sender hun flyttemelding.

Those are less formal, though not exactly identical in tone or structure.