Sjøgangen er rolig.

Sjøgang refers to the movement of the sea, especially the swell or how rough/calm the water is. It is not exactly the same as just sea.

So Sjøgangen er rolig is more like:

• The sea is calm
• The swell is calm
• Sea conditions are calm

depending on context.

Because sjøgangen is the definite form of the noun.

• en sjøgang = a sea movement / a swell / sea state
• sjøgangen = the sea movement / the swell / the sea state

Norwegian often uses the definite form where English would also use the, especially when talking about a specific situation already understood from context, such as the current sea conditions.

In Norwegian, the is often built into the end of the noun instead of being a separate word.

Here:

• en sjøgang = a sea state
• sjøgangen = the sea state

The ending -en is the definite article for many singular nouns.

So English uses two words, but Norwegian often uses one.

Sjøgang is a masculine noun in Bokmål, so its basic forms are:

• en sjøgang
• sjøgangen

Many learners think of masculine and feminine together as common gender, because they behave similarly in many places. In practical terms, the important thing here is that the noun takes en in the indefinite singular and -en in the definite singular.

Because rolig is the correct adjective form here when it is used after er with a singular noun.

This is called a predicate adjective. In Norwegian, predicate adjectives agree mainly with gender and number, not with definiteness in the same way English learners might expect.

Here the subject is singular, so rolig is correct:

• Sjøgangen er rolig.

You would see rolige with plural:

• Bølgene er rolige. = The waves are calm.

It can mean both, depending on context.

Common meanings of rolig include:

• calm
• quiet
• peaceful

In Sjøgangen er rolig, the natural meaning is calm, because it describes the sea conditions.

Er means is / am / are. It is the present tense of å være = to be.

Unlike English, Norwegian does not change the verb for different persons:

• jeg er = I am
• du er = you are
• han er = he is
• vi er = we are

So er is used for all of them in the present tense.

Yes. Norwegian very often makes compound nouns by joining words together.

Here:

• sjø = sea
• gang = movement / motion / course

Together, sjøgang becomes a set expression meaning something like sea motion, swell, or sea state.

This is very common in Norwegian, so learners should get used to seeing long compound words.

A few helpful points:

• sj sounds roughly like sh in English
• ø has no exact English equivalent, but it is somewhat like the vowel in British English bird without a strong r
• ng sounds like the ng in sing

So sjøgangen is approximately:

shø-gang-en

That is only an approximation, but it points you in the right direction.

Yes. This is the standard pattern:

• subject + verb + adjective/complement

So:

• Sjøgangen = subject
• er = verb
• rolig = complement

It is very similar to English The sea is calm.

Yes, but the meaning shifts slightly.

• Havet er rolig = The sea is calm
• Sjøen er rolig = The sea is calm
• Sjøgangen er rolig = The swell / sea motion / sea state is calm

So sjøgangen focuses more specifically on the movement and conditions of the water, not just the sea as a place. That can sound a bit more precise or maritime.