Hjertet er viktig.

Because hjertet is the definite form of the noun, meaning the heart.

• et hjerte = a heart
• hjertet = the heart

In Norwegian, the definite article is usually added to the end of the noun instead of being a separate word like English the.

Since the sentence is talking about the heart, Norwegian uses hjertet.

In Norwegian, the is often built into the noun itself.

So instead of saying something like the heart, Norwegian usually says:

• hjerte = heart
• hjertet = the heart

This is very normal in Norwegian. The ending -et here shows that the noun is definite.

Hjerte is a neuter noun in Norwegian.

Its basic forms are:

• et hjerte = a heart
• hjertet = the heart

Yes, the gender matters because it affects things like:

• which article you use (et)
• how adjectives may behave in some contexts

In this sentence, knowing that hjerte is neuter helps explain why the indefinite form is et hjerte.

Er is the present tense of å være, which means to be.

So here:

• hjertet er viktig = the heart is important

Unlike English, Norwegian does not change the verb depending on the subject:

• jeg er = I am
• du er = you are
• han er = he is
• vi er = we are

So er works for all persons in the present tense.

Viktig is the adjective meaning important.

In this sentence it comes after er, so it is being used predicatively:

• Hjertet er viktig. = The heart is important.

A useful thing to know is that adjectives in Norwegian do not always change in obvious ways in every sentence. With viktig, the form stays viktig here.

Compare:

• et viktig organ = an important organ
• hjertet er viktig = the heart is important

So the form viktig is exactly what you should expect here.

Yes, in this sentence it is very similar to English:

• Hjertet = subject
• er = verb
• viktig = adjective/complement

So the structure is:

subject + verb + adjective

That makes this a very straightforward sentence for English speakers.

A simple learner-friendly guide:

• hj is usually pronounced like English y in yes
• the h is not pronounced clearly here
• hjertet sounds roughly like YER-te or YAR-te, depending on accent

So you should not pronounce it like h-yer-tet with a strong h.

Also, the ending -et is usually unstressed.

A simple approximation is VIK-ti.

A few helpful notes:

• the first syllable is stressed: VIK-
• the written g at the end is not pronounced like a strong English g
• in many accents, it sounds more like vikti

So don’t say it like vik-tig with a hard final g.

Yes, you could, but it means something slightly different.

• Hjertet er viktig = the heart is important
• Et hjerte er viktig = a heart is important

The first sounds like you are talking about the heart in a general or specific sense. The second sounds more like you are talking about a heart as one example or as a member of a class.

So the original sentence uses the more natural form for saying the heart.

Yes. Like English heart, hjerte/hjertet can be used both:

• literally: the organ in the body
• metaphorically: the emotional heart, center, or core

Without more context, the sentence could be understood in either way, though many learners will first read it as the physical heart.

Yes, Hjertet er viktig. is standard Bokmål.

It is also easy to understand in Norwegian generally, even if some dialects or Nynorsk forms may look different. For a learner, this is a normal and useful Bokmål sentence.

The dictionary form is hjerte.

When you look up nouns in Norwegian dictionaries, you usually look for the indefinite singular form, often together with the article:

• et hjerte

Then from that you can build:

• hjertet = definite singular
• hjerter = indefinite plural
• hjertene = definite plural

So if you want to find hjertet in a dictionary, search for hjerte.