Svaet er mindre bratt.

Svaet is the definite form of et sva.

A sva is a smooth, sloping rock surface or rock slab, often used about natural rock in outdoor or hiking contexts. So svaet means the rock slab or the sloping rock face.

It is a fairly specific nature word, not one of the most basic everyday nouns.

Because in Norwegian, the definite article is usually attached to the end of the noun.

So:

• et sva = a rock slab
• svaet = the rock slab

This is very common in Norwegian:

• et hus → huset
• et fjell → fjellet

So svaet already includes the idea of the.

Er is the present tense of å være, which means to be.

So the sentence structure is:

• Svaet = subject
• er = is
• mindre bratt = description of the subject

In other words, er works just like is in English.

Here, mindre means less.

It is placed before the adjective bratt to make the meaning less steep:

• bratt = steep
• mindre bratt = less steep

So mindre is modifying the adjective, not the noun.

Because these mean different things:

• brattere = steeper
• mindre bratt = less steep

So Norwegian, like English, can compare in two different directions:

• more/steeper
• less

You should not combine them. So mindre brattere would be wrong, just like less steeper would be wrong in English.

Because the sentence does not say what it is being compared to. It only says that it is less steep, with the comparison understood from context.

If you want to say what it is less steep than, Norwegian uses enn:

• Svaet er mindre bratt enn stien.
• The rock slab is less steep than the path.

So enn appears only when the second part of the comparison is stated explicitly.

Because it is being used after er, as a predicate adjective.

In a sentence like this, Norwegian usually uses the basic singular form after er:

• Veien er bratt.
• Fjellet er bratt.
• Svaet er bratt.

With bratt, the form looks the same here, so there is nothing extra added.

A learner may notice other forms in other contexts, for example before a noun:

• en bratt bakke = a steep hill
• det bratte fjellet = the steep mountain

But in this sentence, bratt is the normal form.

Yes. This is a very standard Norwegian main clause.

The order is:

• Svaet = subject
• er = finite verb
• mindre bratt = complement

So it follows the normal pattern subject + verb + rest of the sentence.

This is one of the most basic and common sentence patterns in Norwegian.