Rabattperioden reduserer prisøkningen.

Because Norwegian very often forms compound nouns as a single word.

So:

• rabatt = discount
• periode = period

Together they become rabattperiode = discount period.

Then the definite ending is added:

• rabattperiode = a discount period
• rabattperioden = the discount period

This is very normal in Norwegian. English often writes similar ideas as separate words, but Norwegian usually joins them.

It is the definite article attached to the noun.

In Norwegian, instead of usually putting the in front, you often add a definite ending to the noun itself:

• en rabattperiode = a discount period
• rabattperioden = the discount period

So -en here means the.

Because Norwegian commonly marks definiteness by adding it to the noun.

Compare:

• English: the discount period
• Norwegian: rabattperioden

The same happens with prisøkningen:

• en prisøkning = a price increase
• prisøkningen = the price increase

So both nouns are definite without needing a separate word like English the.

For the same reason: it is a compound noun.

It is built from:

• pris = price
• økning = increase

Together:

• prisøkning = price increase

Then the definite ending is added:

• prisøkningen = the price increase

This is a very common Norwegian pattern. When you see a long noun, it is often made of smaller parts joined together.

Because Norwegian verbs do not change by person the way English verbs sometimes do.

In the present tense, redusere becomes reduserer for all subjects:

• jeg reduserer
• du reduserer
• han reduserer
• vi reduserer
• de reduserer

So reduserer is just the normal present-tense form.

The infinitive is å redusere = to reduce.

Common forms are:

• å redusere = to reduce
• reduserer = reduce / reduces
• reduserte = reduced
• har redusert = have/has reduced

So in this sentence, reduserer is the present tense.

In this sentence, rabattperioden is the subject.

The normal Norwegian word order in a main clause is:

subject + verb + object

So here:

• Rabattperioden = subject
• reduserer = verb
• prisøkningen = object

That gives the pattern:

Rabattperioden reduserer prisøkningen.

Because in a simple main clause, Norwegian often uses the same basic order as English:

Subject + Verb + Object

So this sentence feels familiar structurally.

However, Norwegian also follows the V2 rule, which means the finite verb is usually in the second position in main clauses. In this sentence, that happens naturally because the subject comes first:

• Rabattperioden = first position
• reduserer = second position

It is singular definite.

Breakdown:

• prisøkning = a price increase
• prisøkningen = the price increase

Plural would be:

• prisøkninger = price increases
• prisøkningene = the price increases

So this sentence talks about one specific price increase, not several.

Not necessarily.

This sentence says that the discount period reduces the increase in price. That means the increase becomes smaller than it otherwise would be.

So the nuance is important:

• prisfall would mean a price drop
• prisøkning means a price increase

If something reduserer prisøkningen, it does not automatically mean prices are falling. It means the rise is being reduced.

Because the sentence is referring to specific things, not general ones.

Compare:

• En rabattperiode reduserer en prisøkning.
  = a discount period reduces a price increase
  This sounds more general or less specific.

• Rabattperioden reduserer prisøkningen.
  = the discount period reduces the price increase
  This refers to particular, known things.

So the definite form makes the sentence sound more specific and concrete.

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

A rough way to approach it is:

• shape your lips somewhat like you would for o
• but try to place your tongue more like an e sound

In prisøkningen, the ø appears in økning.

You do not need a perfect accent at first. What matters most is recognizing that ø is its own vowel and is different from o and e.

Usually:

• rabattperioden: the main stress is typically on -batt- in rabatt
• reduserer: the stress is usually on -se-
• prisøkningen: the stress usually falls on the first part of the compound, pris

A useful general rule is that in Norwegian compounds, the first element often carries the main stress. So in prisøkning, the stress is on pris.

Yes, in some varieties.

That form is common in Nynorsk and also appears in some dialect-influenced writing. The sentence you were given, however, is standard Bokmål:

• Rabattperioden reduserer prisøkningen. = Bokmål
• Rabattperioda reduserer prisøkninga. = Nynorsk-style forms

If you are learning Bokmål, stick with -en here:

• rabattperioden
• prisøkningen

Yes. The ending -ning often forms a noun from a verb or verbal idea.

Here:

• å øke = to increase
• økning = increase

So prisøkning literally means something like price increase.

This pattern is useful in many Norwegian words, and recognizing endings like -ning can help you guess meanings.