Katten klør seg og biter i halsbåndet.

In Norwegian, the definite article is often attached to the end of the noun.

• katt = cat
• katten = the cat

So katten means the cat. This is very common in Norwegian:

• bok = book
• boka / boken = the book

Here, -en is the definite ending for a singular masculine/common-gender noun in Bokmål.

Klør is the present tense of å klø, which means to scratch.

So:

• å klø = to scratch
• klør = scratch / is scratching

In this sentence, katten klør seg means the cat scratches itself or the cat is scratching itself.

A useful thing to remember is that many Norwegian present-tense verbs end in -r:

• å bite → biter
• å klø → klør

Seg is the reflexive pronoun, meaning himself / herself / itself / themselves, depending on the subject.

In Katten klør seg, the cat is doing the action to itself, so Norwegian uses seg.

Compare:

• Katten klør seg = The cat scratches itself
• Katten klør ham = The cat scratches him

So seg shows that the subject and the object are the same.

It can mean any of those. Norwegian seg does not change for gender the way English does.

So with different subjects:

• Han klør seg = He scratches himself
• Hun klør seg = She scratches herself
• Katten klør seg = The cat scratches itself

That can feel strange to English speakers at first, because English uses different words, but Norwegian uses the same reflexive form.

Because seg by itself is already enough.

• seg = normal reflexive form
• seg selv = himself/herself/itself with extra emphasis, like itself personally or itself and not something else

So:

• Katten klør seg = the normal, natural version
• Katten klør seg selv = possible, but more emphatic

In most ordinary sentences, seg alone is the usual choice.

Because Norwegian often uses bite i when talking about biting into, onto, or at something.

So:

• biter i halsbåndet = bites at the collar / bites into the collar / is chewing on the collar

This is a very natural way to say it in Norwegian. The preposition i helps give the sense that the teeth are going into or onto the object.

English does not always use a preposition in the same way, so this is something learners often just have to get used to as a word combination:

• å bite i noe = to bite something / bite into something / bite at something

Halsbåndet is the definite form, meaning the collar.

• et halsbånd = a collar
• halsbåndet = the collar

The sentence is talking about a specific collar, not just any collar. Most likely it is the collar the cat is wearing, so Norwegian uses the definite form.

This is very natural when the object is already understood from context.

Yes, sitt halsbånd is possible, but it is not exactly the same in feel.

• halsbåndet = the collar
• sitt halsbånd = its own collar

Norwegian often prefers the definite form when ownership is obvious from context. So biter i halsbåndet sounds very natural.

Using sitt would put more focus on the fact that it is the cat’s own collar:

• Katten biter i sitt halsbånd = The cat is biting its own collar

That is correct, but a little more explicit.

Because the same subject, katten, applies to both verbs.

The sentence is really structured like this:

• Katten
  • klør seg
• og
• biter i halsbåndet

In English, we also often do this:

• The cat scratches itself and bites the collar

We do not have to repeat the cat before bites. Norwegian works the same way here.

So this is not two fully separate sentences. It is one sentence with one subject and two coordinated verb phrases.

Good question. Klør can indeed mean different things depending on context:

• klør as a verb = scratches
• klør as a noun = claws or talons

In this sentence, it is clearly a verb because it comes right after the subject Katten and is followed by seg:

• Katten klør seg = The cat scratches itself

If it were the noun, the sentence structure would be different.

So this is one of those cases where grammar and context tell you which meaning is intended.

The most important thing for English speakers is the vowel ø, which does not exist in standard English.

A rough guide:

• klør sounds approximately like klur or klir said with rounded lips, but neither English version is exact
• the r is there at the end, though pronunciation varies by dialect

A simple way to practice ø is:

1. Say an ee-like vowel
2. Round your lips as if saying oo
3. Keep the tongue position more forward than for oo

Also, do not confuse:

• klor with o
• klør with ø

That vowel difference matters in Norwegian.