Den månatliga kostnaden är för hög.

Den is the definite article used with common-gender nouns (also called en-words) in Swedish.

The noun here is kostnad (cost), and it is an en-word:

• en kostnad = a cost
• kostnaden = the cost

When a definite noun has an adjective before it, Swedish usually uses a double definite structure:

• den månatliga kostnaden

Literally, that is:

• den = the
• månatliga = monthly
• kostnaden = the cost

So Swedish often says something like the monthly the-cost, where English only says the monthly cost.

Because the adjective comes before a definite noun.

In Swedish, adjectives often change form depending on whether the noun is:

• common gender
• neuter
• plural
• definite

Here, kostnaden is definite singular, so the adjective usually takes -a:

• en månatlig kostnad = a monthly cost
• den månatliga kostnaden = the monthly cost

So:

• månatlig = indefinite singular common gender
• månatliga = definite form (and also plural in many cases)

That is why månatliga is correct here.

Because the noun is definite: the cost, not just a cost.

Swedish often marks definiteness by adding an ending to the noun:

• en kostnad = a cost
• kostnaden = the cost

For many common-gender nouns, the definite singular ending is -en.

So:

• kostnad = cost
• kostnaden = the cost

In this sentence, the speaker is talking about a specific cost, so the definite form is used.

This is a very common Swedish pattern called double definiteness.

When you have:

• a definite noun
• with an adjective before it

Swedish usually uses:

1. a definite article (den, det, or de)
2. the adjective in its definite form
3. the noun in its definite form

So:

• den månatliga kostnaden

This is normal Swedish grammar.

Compare:

• en hög kostnad = a high cost
• den höga kostnaden = the high cost

English only marks definiteness once with the, but Swedish usually marks it more than once in this structure.

Är means is. It is the present tense of vara (to be).

So:

• är = is

In the sentence:

• Den månatliga kostnaden är för hög = The monthly cost is too high

This is one of the most common Swedish verbs, and är is used exactly the way is is used in English.

Here, för means too, not for.

In front of an adjective or adverb, för often means excessively or more than is acceptable:

• för hög = too high
• för dyr = too expensive
• för sent = too late

So in this sentence:

• är för hög = is too high

This is a very important use of för in Swedish.

Because hög is describing kostnaden, and kostnaden is a singular common-gender noun.

When an adjective comes after är and describes the subject, it is a predicate adjective, and it still usually agrees with the noun:

• common gender singular: hög
• neuter singular: högt
• plural: höga

Since kostnaden is an en-word and singular, the correct form is:

• kostnaden är hög = the cost is high

Compare:

• Priset är högt = The price is high
  (pris is a neuter noun, an ett-word)
• Kostnaderna är höga = The costs are high

So hög is correct because kostnaden is singular and common gender.

No, that would be ungrammatical in standard Swedish.

If you use den before the adjective, the noun normally also has to be definite:

• den månatliga kostnaden ✅
• den månatliga kostnad ❌

If the noun is indefinite, then you would say:

• en månatlig kostnad = a monthly cost

So the two correct patterns are:

• en månatlig kostnad = a monthly cost
• den månatliga kostnaden = the monthly cost

You should not mix the definite article with an indefinite noun form.

Because this is a normal Swedish main clause:

• Den månatliga kostnaden = subject
• är = verb
• för hög = complement

Swedish main clauses usually follow V2 word order, meaning the finite verb comes early in the sentence, typically in the second position.

Here the structure is straightforward:

• Subject: Den månatliga kostnaden
• Verb: är
• Complement: för hög

So it works much like English:

• The monthly cost is too high

Yes. Månatlig is a normal formal or neutral adjective meaning monthly.

You may also sometimes see related expressions, depending on context, such as:

• per månad = per month
• månadskostnad = monthly cost / cost per month

So this sentence is perfectly natural, especially in formal contexts like bills, subscriptions, budgets, contracts, or business writing.

Yes, that is also possible.

• Den månatliga kostnaden är för hög
• Månadskostnaden är för hög

Both can mean roughly The monthly cost is too high.

The difference is mainly in style:

• den månatliga kostnaden sounds a bit more descriptive and formal
• månadskostnaden uses a compound noun, which Swedish does very often

Both are natural, but the original sentence is completely standard.

A rough pronunciation guide is:

den moh-nat-lee-ga KOST-nah-den air fur hoeg

A few notes:

• månatliga has stress early in the word
• kostnaden has main stress on kost
• är is pronounced somewhat like air
• hög has a vowel sound that does not exist exactly in English; it is similar to a rounded version of the vowel in French bleu or German schön

If you want, a more careful rough guide is:

den MOH-nat-lee-ga KOST-na-den ehr fur hoog

But the best way to learn this is by listening to native audio, because Swedish vowel sounds are very important.

The sentence follows this pattern:

definite noun phrase + verb + degree word + adjective

More specifically:

• Den månatliga kostnaden = definite noun phrase
• är = verb
• för = degree word meaning too
• hög = adjective

So you can build similar sentences like this:

• Den här bilen är för dyr = This car is too expensive
• Hyreskostnaden är för hög = The rent cost is too high
• Temperaturen är för låg = The temperature is too low

This makes the sentence a very useful model to learn from.