Månedsavgiften er lav.

Because Norwegian very often forms compound nouns by writing them as a single word.

Here, månedsavgiften is made up of:

• måned = month
• avgift = fee / charge
• plus linking -s-
• plus the definite ending -en

So the structure is roughly:

• måned + s + avgift + en
• the monthly fee

This is very normal in Norwegian. English often uses separate words where Norwegian prefers one compound word.

The -s- is a linking sound/letter often used in Norwegian compounds. It does not usually have a separate meaning by itself.

So:

• måned = month
• måneds- = monthly / month-related
• avgift = fee

Together, månedsavgift means monthly fee.

You cannot always predict perfectly when Norwegian uses a linking -s-, so it is often best to learn compound nouns as whole words.

Because -en is the definite singular ending for many masculine nouns in Norwegian.

• en avgift = a fee
• avgiften = the fee

In this sentence, the noun is definite, so månedsavgiften means the monthly fee, not just a monthly fee.

Yes, avgift is normally treated as a masculine noun in Bokmål:

• en avgift
• avgiften

Since the head noun in the compound is avgift, the whole compound follows that noun’s gender:

• en månedsavgift
• månedsavgiften

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

So:

• er = is / are / am depending on context

In Månedsavgiften er lav, it simply means:

• The monthly fee is low

Norwegian verbs do not change depending on the subject the way English verbs sometimes do. So er stays the same with jeg, du, han, vi, etc.

Because adjectives in Norwegian often agree with the noun they describe.

Here, månedsavgiften is:

• singular
• definite
• based on a masculine noun

In a sentence like this, after er, the adjective is usually in the base form for singular masculine/feminine nouns:

• Avgiften er lav = The fee is low

Compare:

• Huset er lavt = The house is low
  
  • hus is neuter, so lavt
• Prisene er lave = The prices are low
  
  • plural, so lave

So lav is correct here because the subject is a singular non-neuter noun.

It is an adjective.

It describes the noun månedsavgiften. In other words, it tells you what the monthly fee is like.

This is called a predicative adjective because it comes after the verb er:

• Månedsavgiften er lav

It is not acting as an adverb here.

This is the normal basic Norwegian sentence order:

• Subject + verb + adjective/complement

So:

• Månedsavgiften = subject
• er = verb
• lav = complement/adjective

This is the same basic order as in English:

• The monthly fee is low

You would normally say:

• En månedsavgift er lav

But in real usage, that sentence is a bit unusual unless you are speaking very generally. More often, you would say:

• Månedsavgiften er lav = The monthly fee is low

That sounds more natural when talking about a specific fee, such as the one for a service, membership, or subscription.

A rough guide for an English speaker is:

• MOH-neds-ahv-gif-ten

A few helpful points:

• å sounds like a long vowel somewhat like the vowel in British more, though not exactly the same
• d in måned can be softer than English learners expect
• the stress is usually on the first part of the compound: MÅNEDSavgiften

You do not need perfect pronunciation right away, but it helps to recognize that Norwegian compounds are usually spoken as one unit.

Sometimes, yes, but lav and billig are not exactly the same.

• lav = low
• billig = cheap

For prices, fees, rates, and amounts, Norwegian often uses lav:

• Prisen er lav = The price is low
• Avgiften er lav = The fee is low

Billig is more about something being inexpensive in a broader sense:

• Bilen er billig = The car is cheap/inexpensive

So lav is the more natural choice with avgift.

No, that would not sound correct in standard Norwegian.

If you want an indefinite noun, you normally need the article:

• En månedsavgift er lav

If you want a definite noun, you use the definite ending:

• Månedsavgiften er lav

Bare månedsavgift by itself is not correct as the subject here.

A possible plural form would be:

• månedsavgifter = monthly fees
• månedsavgiftene = the monthly fees

Then the sentence would change like this:

• Månedsavgiftene er lave = The monthly fees are low

Notice the adjective agreement:

• singular: lav
• plural: lave