Kilometergodtgjørelsen er høy.

Because Norwegian normally writes compound nouns as a single word.

Here, kilometergodtgjørelsen is built from:

• kilometer = kilometre / kilometer
• godtgjørelse = compensation, reimbursement, allowance
• -en = the definite ending

So the whole word means something like the mileage allowance or the per-kilometre reimbursement.

This is very normal in Norwegian, even when the result looks long to an English speaker.

-en is the definite singular ending, roughly equivalent to English the.

So:

• kilometergodtgjørelse = mileage allowance / kilometre reimbursement
• kilometergodtgjørelsen = the mileage allowance / the kilometre reimbursement

Norwegian often adds definiteness to the end of the noun instead of using a separate word like English the.

Because in Norwegian, definiteness is usually built into the noun itself.

English says:

• the mileage allowance

Norwegian says:

• kilometergodtgjørelsen

The the idea is already included in -en, so you do not add a separate article in this sentence.

Er means is.

It is the present tense of å være = to be.

So:

• Kilometergodtgjørelsen er høy = The mileage allowance is high

This is one of the most common Norwegian verbs, and er is used very frequently.

Because the adjective agrees with the noun.

In this sentence, kilometergodtgjørelsen is singular and treated as a common-gender noun in Bokmål, so the adjective form is høy.

Compare:

• common gender singular: godtgjørelsen er høy
• neuter singular: beløpet er høyt
• plural: satsene er høye

So høy is the correct form here.

Here høy means high in the sense of large or generous, not physically tall.

So it means the reimbursement rate is high, not that anything has height.

This is similar to English:

• a high salary
• high costs
• a high allowance

No, this is a very basic Norwegian sentence pattern:

• subject + verb + adjective/complement

So:

• Kilometergodtgjørelsen = subject
• er = verb
• høy = complement

It works just like English:

• The mileage allowance is high

Yes, but then the sentence would be structured differently.

The original sentence uses predicative adjective placement:

• Kilometergodtgjørelsen er høy = The mileage allowance is high

If you want the adjective before the noun, that is attributive use:

• en høy kilometergodtgjørelse = a high mileage allowance

So both are possible, but they are used in different sentence structures.

In Bokmål, many nouns can be treated in more than one gender pattern depending on style. In this sentence, it is clearly being treated as an en-word because the definite form is -en:

• kilometergodtgjørelsen

For a learner, the important thing is:

• this sentence uses the common-gender pattern
• therefore the adjective form is høy

Most likely as reimbursement paid per kilometre, especially for work travel or use of a private car for business purposes.

So a native speaker would usually connect it with things like:

• travel reimbursement
• mileage allowance
• compensation per kilometre driven

Even if the exact English translation can vary, the Norwegian word clearly points to that kind of payment or allowance.