Rederiet kontrollerer overfartstiden.

Rederiet means the shipping company, the shipping line, or in some contexts the ferry operator.

The base noun is et rederi = a shipping company.
It is a neuter noun, and in Norwegian the definite article is often added to the end of the noun:

• et rederi = a shipping company
• rederiet = the shipping company

So the ending -et here is the definite article for a singular neuter noun.

Kontrollerer is the present tense of å kontrollere = to control / check / monitor / inspect.

Examples:

• jeg kontrollerer = I control / check
• du kontrollerer = you control / check
• rederiet kontrollerer = the shipping company controls / checks

A useful point for English speakers: in Norwegian, the present tense verb does not change depending on the subject. So you use kontrollerer with I, you, he, we, etc.

It could mean either, depending on context.

In Norwegian, å kontrollere often means:

• to check
• to inspect
• to monitor
• sometimes to control

So this sentence might mean:

• the shipping company controls the crossing time
• the shipping company checks the crossing time
• the shipping company monitors the crossing time

In many real-life contexts, checks or monitors may sound more natural in English than controls.

Overfartstiden is a compound noun.

It breaks down like this:

• overfart = crossing / passage
• tid = time
• tiden = the time

So:

• overfartstid = crossing time / duration of the crossing
• overfartstiden = the crossing time

The last part, tid, is the main noun, and that is why the definite ending goes on the end of the whole compound.

Because Norwegian usually writes compound nouns as one word.

English often separates or hyphenates things that Norwegian joins together.
So where English might say crossing time, Norwegian makes one compound noun:

• overfartstid

Then the definite ending is added to the end:

• overfartstiden

This is very normal in Norwegian. The same pattern appears everywhere:

• tog
  • billett = togbillett
• arbeid
  • tid = arbeidstid
• sommer
  • ferie = sommerferie

Because Norwegian usually expresses definiteness by adding an ending to the noun instead of using a separate word like English the.

In this sentence:

• rederiet = the shipping company
• overfartstiden = the crossing time

So Norwegian does not need a separate the here.

A very important pattern:

• et rederi = a shipping company
• rederiet = the shipping company
• en tid = a time
• tiden = the time

With adjectives, Norwegian often uses both a separate definite word and the noun ending:

• den lange overfartstiden = the long crossing time

Yes, it could be indefinite in another context, but here the definite form suggests a specific crossing time.

Compare:

• Rederiet kontrollerer overfartstiden. = The shipping company checks the crossing time.
• Rederiet kontrollerer en overfartstid. = The shipping company checks a crossing time.

The second version is grammatically possible, but it sounds less natural unless you really mean one crossing time among several possible ones. In many contexts, the definite form is more natural because both speaker and listener know which crossing time is being referred to.

The sentence uses the basic Norwegian main-clause order:

Subject + Verb + Object

• Rederiet = subject
• kontrollerer = verb
• overfartstiden = object

So:

Rederiet kontrollerer overfartstiden.

This is very similar to normal English word order.

A useful extra point: Norwegian main clauses follow the V2 rule, which means the finite verb is in the second position. So if you move something else to the front, the verb still stays second:

• I dag kontrollerer rederiet overfartstiden. = Today, the shipping company checks the crossing time.

Notice that the verb kontrollerer still comes second.

Not necessarily.

Et rederi is a general word for a shipping company or ship-owning company. Depending on context, it could refer to:

• a ferry company
• a cruise line
• a cargo shipping company
• a shipping operator in general

Because the sentence mentions overfartstiden, a ferry or passenger-crossing context is certainly possible, but the word rederi itself is broader than just ferry company.