Girsystemet må justeres.

Because Norwegian usually writes compound nouns as a single word.

So:

• gir = gear
• system = system
• girsystem = gear system / transmission system
• girsystemet = the gear system

This is very common in Norwegian. Where English often uses two words, Norwegian often prefers one compound word.

The ending -et is the definite article attached to the noun.

With system, the pattern is:

• et system = a system
• systemet = the system

Since girsystem is built on system, it keeps the neuter definite ending:

• et girsystem = a gear system
• girsystemet = the gear system

So Norwegian often puts the at the end of the noun instead of using a separate word before it.

In Norwegian, definiteness is often shown with a suffix on the noun itself.

So instead of saying something like the gear system with a separate article, Norwegian says:

• girsystemet

That final -et already means the.

A separate word such as det is not used here because there is no adjective. If you add an adjective, you often get double definiteness, for example:

• det nye girsystemet = the new gear system

Må is the present tense of å måtte, and here it means must or has to.

So:

• må = must / has to

It is a modal verb, like English must, can, should, etc.

Examples:

• Bilen må repareres. = The car must be repaired.
• Girsystemet må justeres. = The gear system must be adjusted.

Because after a modal verb like må, Norwegian normally uses the bare infinitive, without å.

Compare:

• å justere = to adjust
• må justere = must adjust

In this sentence, the passive form is used, so it becomes:

• må justeres = must be adjusted

This is normal after modal verbs.

Because this sentence uses the passive.

Compare:

• Noen må justere girsystemet. = Someone must adjust the gear system.
  
  • active
• Girsystemet må justeres. = The gear system must be adjusted.
  
  • passive

Here, justeres is the passive infinitive used after må.

Why not the others?

• justere would be active: must adjust
• justert is a past participle, used in forms like er justert or blir justert

So må justeres is the correct way to say must be adjusted.

Yes. This is an -s passive form, and it is very common, especially in written, formal, and technical Norwegian.

So:

• justere = adjust
• justeres = be adjusted

This kind of passive is especially common in instructions, manuals, technical writing, and neutral descriptions.

A more explicit alternative is:

• Girsystemet må bli justert.

That also means the gear system must be adjusted.

Very roughly:

• må justeres = shorter, often more formal/technical
• må bli justert = also common, sometimes feels a little more conversational or process-focused

Because Norwegian main clauses follow the V2 rule: the finite verb normally comes in the second position.

Here:

1. Girsystemet = subject
2. må = finite verb
3. justeres = non-finite verb

So the structure is:

• Subject + finite verb + non-finite verb

If something else comes first, the finite verb still stays in second position:

• Nå må girsystemet justeres. = Now the gear system must be adjusted.

That verb-second pattern is a very important feature of Norwegian.

Not in this sentence.

The word gir can be:

• the present tense of å gi = gives
• a noun meaning gear

Here it is part of the compound noun girsystemet, so it is clearly the noun gir = gear.

So this sentence is about a mechanical system, not about the verb to give.

The direct negative form is:

• Girsystemet må ikke justeres.

That usually means:

• The gear system must not be adjusted.

Be careful: in English, does not have to be adjusted is different. In Norwegian, that idea is usually expressed with something like:

• Girsystemet trenger ikke å justeres. = The gear system does not need to be adjusted.

So:

• må ikke = must not
• trenger ikke å = does not need to / does not have to