De gemeente keurt een betalingsregeling goed, mits u het verzoek onderbouwt.

Because the full verb is goedkeuren = to approve, and this is a separable verb.

In a main clause, Dutch often splits separable verbs:

• De gemeente keurt het verzoek goed.
• literally: The municipality approves the request

So:

• keurt = the conjugated verb part
• goed = the separable particle

You will usually see:

• infinitive: goedkeuren
• main clause: keurt ... goed
• past participle: goedgekeurd

Example:

• De gemeente heeft het verzoek goedgekeurd.

De gemeente usually means the municipality or the local authority/council.

In administrative or official Dutch, gemeente often refers to the local government as an institution, not just the town itself.

So in this sentence, de gemeente is the authority making the decision.

Betalingsregeling is a compound noun, which is very common in Dutch.

It is made up of:

• betaling = payment
• regeling = arrangement, scheme, regulation

Together:

• betalingsregeling = payment arrangement or payment plan

Dutch often combines nouns into one long word where English would use two or more words.

Other examples:

• zorgverzekering = health insurance
• belastingaangifte = tax return
• arbeidscontract = employment contract

This is about grammatical gender and articles in Dutch.

• een = a/an, the indefinite article
• het = the for a het-word

So:

• een betalingsregeling = a payment arrangement
• het verzoek = the request

You simply have to learn whether a noun is a de-word or a het-word:

• de gemeente
• het verzoek

That is why the articles are different.

Mits means provided that, as long as, or on condition that.

It introduces a condition. It is fairly common in formal or written Dutch, especially in legal, administrative, or official language.

So:

• De gemeente keurt een betalingsregeling goed, mits u het verzoek onderbouwt. means:
• The municipality approves a payment plan, provided that you substantiate the request.

In less formal Dutch, people might also use:

• als
• op voorwaarde dat

But mits is very natural in formal documents.

Because mits introduces a subordinate clause.

In Dutch subordinate clauses, the conjugated verb normally goes to the end:

• mits u het verzoek onderbouwt

Compare:

Main clause:

• U onderbouwt het verzoek.

Subordinate clause:

• ... mits u het verzoek onderbouwt.

This verb-final pattern is one of the most important word-order rules in Dutch.

Onderbouwen means to substantiate, to support with arguments or evidence, or to justify properly.

In this context, het verzoek onderbouwen means you must explain and support your request with sufficient reasons or documents.

So it is stronger than just asking. It suggests:

• giving evidence
• giving reasons
• providing documentation

It is a common formal word in administrative Dutch.

U is the formal word for you in Dutch.

This sentence is clearly formal and official, so u is the appropriate choice. Government bodies, municipalities, banks, and other institutions often address people with u.

Compare:

• formal: mits u het verzoek onderbouwt
• informal: mits je het verzoek onderbouwt

Because the sentence comes from an official context, u sounds natural and expected.

No. Onderbouwen is not separable.

That is why you do not split it:

• correct: u onderbouwt het verzoek
• not: u bouwt het verzoek onder

By contrast, goedkeuren is separable:

• de gemeente keurt het verzoek goed

So these two verbs behave differently:

• goedkeuren → separable
• onderbouwen → inseparable

Yes, absolutely.

You can say:

• Mits u het verzoek onderbouwt, keurt de gemeente een betalingsregeling goed.

When the subordinate clause comes first, the main clause follows with inversion, so the verb comes before the subject:

• keurt de gemeente not
• de gemeente keurt

This is a very common Dutch word-order pattern.

Dutch does not need a separate word like then in this kind of sentence.

English often allows:

• If you do X, then Y happens.

Dutch can do that in some cases, but here it is not necessary. The structure with mits already clearly expresses the condition:

• mits u het verzoek onderbouwt

So the sentence is complete and natural without an extra word.

It is quite formal and administrative.

Several things make it sound official:

• de gemeente as an institution
• u instead of je
• mits
• onderbouwt
• the compound noun betalingsregeling

This is the kind of Dutch you might see in:

• letters from the municipality
• official websites
• legal or financial communication
• policy documents

In everyday speech, a person might say something simpler, but in official writing this sentence sounds very natural.

The sentence has:

1. a main clause
2. a subordinate clause expressing a condition

Main clause:

• De gemeente keurt een betalingsregeling goed
• subject: De gemeente
• verb: keurt ... goed
• object: een betalingsregeling

Subordinate clause:

• mits u het verzoek onderbouwt
• conjunction: mits
• subject: u
• object: het verzoek
• verb at the end: onderbouwt

So the full pattern is:

[main clause], [conditional subordinate clause]

That is a very common structure in formal Dutch.