Kilden forklarer årsaken og sammenhengen.

Because they are definite singular nouns. In Norwegian, the equivalent of the is often attached to the end of the noun instead of being a separate word.

• kilde = source

• kilden = the source

• årsak = cause / reason

• årsaken = the cause / reason

• sammenheng = connection / context / relationship
• sammenhengen = the connection / context / relationship

This is very common in Norwegian. English uses a separate article (the), but Norwegian often uses a suffix.

Because Norwegian usually marks definiteness by adding it to the noun itself.

So instead of:

• the source
• the cause
• the connection

Norwegian says:

• kilden
• årsaken
• sammenhengen

A separate determiner like den can appear too, but usually only in certain structures, especially with adjectives:

• kilden = the source
• den viktige kilden = the important source

So in your sentence, no extra word is needed.

Forklarer is the present tense of å forklare = to explain.

Examples:

• jeg forklarer = I explain / I am explaining
• du forklarer = you explain
• han forklarer = he explains
• kilden forklarer = the source explains

A useful point for English speakers: Norwegian verbs do not change form depending on the subject in the present tense. The same form forklarer is used with all persons.

No, this sentence has very normal subject–verb–object word order:

• Kilden = subject
• forklarer = verb
• årsaken og sammenhengen = object

So it works much like English:

• The source explains the cause and the connection.

This is one of the easiest Norwegian sentence patterns for English speakers to recognize.

Sammenheng is a very useful Norwegian word, but it can be a little broader than one single English word.

Depending on context, it can mean:

• connection
• relationship
• context
• coherence
• link

So sammenhengen could mean something like:

• the connection
• the relationship
• the context

In this sentence, it probably means that the source explains both:

• why something happens (årsaken), and
• how it is connected to something else (sammenhengen)

Both can relate to reason/cause, but they are not always identical.

• årsak often means cause, especially in a more logical, factual, or formal sense
• grunn often means reason, especially in everyday language

Examples:

• årsaken til brannen = the cause of the fire
• grunnen til at jeg dro = the reason I left

In your sentence, årsaken sounds a bit more analytical or explanatory, which fits well with forklarer.

Because the sentence refers to specific things already known in the context, or treated as identifiable by the speaker.

So the sentence is not talking about just any cause or any connection, but rather:

• the cause
• the connection

This is very natural in Norwegian when referring to something already mentioned, understood, or being discussed in a specific setting.

If the nouns were indefinite, the meaning would change:

• en årsak = a cause
• en sammenheng = a connection

That would sound more general or less specific.

No, not in normal standard Norwegian. Og means and, and it is needed to connect the two nouns:

• årsaken og sammenhengen = the cause and the connection

If you removed og, the sentence would become ungrammatical or very unclear.

The letter å is a separate letter in Norwegian, not just an accented a. It represents a vowel sound that does not exist exactly the same way in English.

• årsak begins with å
• å is pronounced somewhat like the vowel in British more or thought, depending on accent, but not exactly

Also note:

• å as a letter is different from a
• å can also be the infinitive marker meaning to, but here it is simply part of the noun årsak

So in årsaken, the å is just part of the word.

Yes, it can. Words like kilden, forklarer, årsaken, and especially sammenhengen often appear in:

• academic writing
• source analysis
• essays
• reports
• classroom discussion

It sounds more formal and analytical than very casual everyday speech. A native speaker might use it when discussing a text, article, event, or argument.

Yes, but that would usually reflect a dialect form or Nynorsk, not standard Bokmål.

• In Bokmål: kilden
• In Nynorsk: kjelda
• In some spoken dialects, you may also hear forms that differ from Bokmål

So if you are learning standard Bokmål, Kilden forklarer årsaken og sammenhengen is the correct form to focus on.