Hjertestarteren kontrollerer hjerterytmen.

Because both nouns are in the definite singular form, meaning the rather than a/an.

• en hjertestarter = a defibrillator

• hjertestarteren = the defibrillator

• en hjerterytme = a heart rhythm
• hjerterytmen = the heart rhythm

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

In Norwegian, the definite article is often added as a suffix to the noun.

So instead of saying something like the heart rhythm with a separate article, Norwegian usually says hjerterytmen, where -en means the.

This is one of the most important differences from English noun structure.

The word order is:

subject + verb + object

• Hjertestarteren = subject
• kontrollerer = verb
• hjerterytmen = object

So it works very much like English:

The defibrillator controls the heart rhythm.

This is the normal word order in a simple main clause.

No. Kontrollerer is the present tense form of the verb.

• å kontrollere = to control / to check / to monitor
• kontrollerer = controls / is controlling / checks, depending on context

In Norwegian, present tense verbs often end in -r.

Examples:

• å snakke → snakker
• å jobbe → jobber
• å kontrollere → kontrollerer

It can mean different things depending on context. In a medical or technical sentence like this, kontrollerer often means:

• checks
• monitors
• sometimes controls

So the exact English translation depends on what the device is doing. If the meaning has already been provided to the learner, the important thing grammatically is that kontrollerer is the present tense verb.

Yes. Norwegian very often forms compound nouns, and they are usually written as one word.

Here:

• hjerte = heart
• starter = starter

Together:

• hjertestarter = defibrillator

Likewise:

• hjerte = heart
• rytme = rhythm

Together:

• hjerterytme = heart rhythm

This is very common in Norwegian, much more so than in English.

In compounds, Norwegian often uses the full noun stem, and sometimes a linking pattern appears that may not feel obvious to English speakers.

Here:

• hjerte
  • starter → hjertestarter
• hjerte
  • rytme → hjerterytme

You do not need to translate each part too mechanically every time. The important thing is to get used to recognizing common compounds built from hjerte.

A learner-friendly approximation is:

YER-teh-star-teh-ren

A few useful points:

• hj at the start is usually pronounced like y in many dialects
• j is like English y
• r may sound different depending on dialect
• the final -en is usually a short unstressed ending

You do not need perfect pronunciation immediately, but it helps to notice that hj is not pronounced like English h + j.

A rough learner-friendly version is:

YER-teh-RYT-men

Useful points:

• again, hj sounds roughly like y
• y in rytme is a Norwegian vowel that does not exist in normal English pronunciation
• the stress is usually on the first part of the compound element: RYT

The vowel y may be difficult at first. It is similar to a rounded ee sound.

Both hjertestarter and hjerterytme are commonly treated as masculine nouns, which is why their definite singular form ends in -en:

• en hjertestarter → hjertestarteren
• en hjerterytme → hjerterytmen

In Bokmål, many feminine nouns can also be treated as masculine, but that is not the issue here: these are standard en nouns.

Yes, but it would mean something slightly different.

• Hjertestarteren kontrollerer hjerterytmen = The defibrillator controls/checks the heart rhythm
• Den hjertestarteren kontrollerer hjerterytmen = That defibrillator controls/checks the heart rhythm

Adding den usually makes it more specific or contrastive, like pointing something out.

No, not in a normal sentence like this. Norwegian normally requires an explicit subject.

So you say:

• Hjertestarteren kontrollerer hjerterytmen

You would not normally omit hjertestarteren if it is the subject of the sentence.

This sentence is Bokmål.

A key clue is the present tense verb form kontrollerer, which is fine in Bokmål, and the overall noun forms also fit normal Bokmål usage.

The indefinite version would be:

En hjertestarter kontrollerer en hjerterytme.

But this sounds less natural in many contexts, because English and Norwegian often prefer definite forms when talking about specific medical functions.

More natural indefinite uses might be:

• En hjertestarter kan kontrollere hjerterytmen.
• En hjertestarter brukes til å kontrollere hjerterytmen.

In this sentence, the first noun phrase is the subject because of the normal Norwegian word order:

Hjertestarteren + kontrollerer + hjerterytmen

So hjertestarteren is the thing performing the action, and hjerterytmen is what the action is directed at.

English speakers usually find this easy because the structure is very similar to English.