Pustestøtten er stabil.

Because Norwegian usually writes compound nouns as one word.

So pustestøtten is built from:

• pust(e)- = breath / breathing
• støtte = support

Together they form pustestøtte = breath support, and then the definite ending is added:

• pustestøtte = breath support
• pustestøtten = the breath support

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

The -en is the definite singular ending, so it means the.

Compare:

• pustestøtte = breath support / a breath support
• pustestøtten = the breath support

In Norwegian, the definite article is often attached to the end of the noun instead of being a separate word in front, unlike English.

Yes, in many contexts, pustestøtta is also possible in Bokmål.

That is because støtte is a noun that can often be treated as feminine, and many feminine nouns in Bokmål may appear either with:

• -a definite ending: pustestøtta
• -en definite ending: pustestøtten

So the sentence you were given uses a perfectly normal Bokmål form, but pustestøtta er stabil could also be correct depending on style, preference, or dialect.

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

So:

• er = is / are / am depending on context

In this sentence, it links the subject to a description:

• Pustestøtten = the breath support
• er = is
• stabil = stable

This is the same basic pattern as in English:

• The breath support is stable.

Because the adjective agrees with the noun.

Here, pustestøtten is singular and not neuter, so the adjective takes the basic form:

• stabil

Compare:

• en stabil tone = a stable tone
• pustestøtten er stabil = the breath support is stable

But with a neuter singular noun, you usually get -t:

• et mønster = a pattern
• mønsteret er stabilt = the pattern is stable

And in plural:

• forholdene er stabile = the conditions are stable

So stabil is the correct agreement form here.

Yes. Even when the adjective comes after er, it still agrees with the noun.

This is called a predicative adjective. Norwegian still marks agreement there:

• Boken er ny = the book is new
• Huset er nytt = the house is new
• Bilene er nye = the cars are new

So in Pustestøtten er stabil, the adjective is after the verb, but it still matches the noun in number and gender pattern.

No, this is the normal word order for a simple main clause:

• Subject + verb + adjective/complement

So:

• Pustestøtten = subject
• er = verb
• stabil = complement

This is very straightforward Norwegian word order.

The main thing to remember is that Norwegian usually follows the V2 rule in main clauses, meaning the finite verb is in the second position. In this sentence, the subject comes first, so the verb naturally comes second.

Usually, not in the same specific sense.

Pustestøtten er stabil refers to a particular breath support, probably one already being discussed.

If you say Pustestøtte er stabil, it sounds odd in most contexts, because a bare singular noun like that is less natural here.

For a general statement, Norwegian often prefers something like:

• Pustestøtte er viktig. = Breath support is important.

That works better because it talks about the concept in general. But your original sentence sounds like it is describing a specific case, so the definite form pustestøtten makes sense.

The letter ø is a vowel that does not exist in standard English.

A rough guide:

• It is somewhat like the vowel in British English bird or nurse, but with rounded lips
• It is also similar to German ö or French eu

In this sentence, you hear it in:

• støt in pustestøtten

A rough pronunciation guide for the whole sentence could be:

• PU-ste-støt-ten er sta-BIIL

That is only approximate, but it helps with the main stress. The most important new sound for many English speakers here is ø.

Stabil is an adjective, and it is very similar to the English word stable in both form and meaning.

It is one of many Norwegian adjectives that look familiar to English speakers because they come from international vocabulary.

Its common forms are:

• stabil = singular common gender
• stabilt = singular neuter
• stabile = plural / definite contexts

So in your sentence, stabil is simply the adjective describing pustestøtten.