Frygten forsvinder langsomt.

Frygt is the basic noun form, meaning fear.
Frygten is the definite singular form, meaning the fear.

In Danish, the definite article is usually attached to the end of the noun:

• en frygt = a fear
• frygten = the fear

So Danish normally uses frygten, not en frygten.

Frygt is a common gender noun in Danish, so its indefinite form is en frygt.

For common gender nouns, the definite singular ending is usually -en:

• en bil → bilen
• en frygt → frygten

If it were a neuter noun, the definite ending would usually be -et instead.

Usually frygten means the fear — a fear that is already understood from the context.

So this sentence most naturally refers to a particular fear, not just the abstract idea of fear in general.

If you wanted to talk about fear more generally, Danish can also use frygt without the definite ending in some contexts, depending on the sentence.

Yes. Forsvinder is the present tense of at forsvinde.

• at forsvinde = to disappear
• forsvinder = disappears / is disappearing

Like most Danish verbs in the present tense, it ends in -r.

Also, Danish verbs do not change for person:

• jeg forsvinder
• du forsvinder
• han/hun forsvinder

The verb form stays the same.

Yes. Danish often uses the simple present where English might use either:

• disappears
• is disappearing

So Frygten forsvinder langsomt can mean:

• The fear disappears slowly
• The fear is disappearing slowly

The exact nuance depends on context.

If Danish wants to emphasize an ongoing process more clearly, it can use a different structure, such as er ved at forsvinde.

Because langsomt is being used as an adverb, modifying the verb forsvinder.

The adjective is langsom = slow.
The adverb is langsomt = slowly.

So:

• en langsom proces = a slow process
• den forsvinder langsomt = it disappears slowly

The -t here is not agreeing with frygten. It shows that the word is functioning adverbially.

The word order is:

• Frygten = subject
• forsvinder = finite verb
• langsomt = adverb

So the structure is:

subject + verb + adverb

This is a very normal, neutral Danish main clause.

Yes, but it changes the feel of the sentence.

The neutral version is:

Frygten forsvinder langsomt.

You can also say:

Langsomt forsvinder frygten.

That is grammatically possible, but it sounds more literary, dramatic, or stylistically marked.

Notice that when langsomt comes first, the verb still stays in the second position. This is part of the Danish V2 word order rule for main clauses.

Because Danish usually puts the definite article onto the noun itself.

So instead of a separate word like English the fear, Danish normally says:

frygten

This is one of the big differences between English and Danish noun structure.

A separate definite word such as den is mainly used in certain other constructions, especially when an adjective comes before the noun:

• frygten = the fear
• den store frygt = the big fear

A rough guide:

• frygten: the y is not like English y. It is closer to the vowel in German ü or French u. The ending -en is usually weak.
• forsvinder: the stress is on -svin-, so roughly for-SVIN-er.

A few useful points:

• Danish y is a special vowel that English speakers usually need practice with.
• The final -er and -en are often pronounced lightly.
• Danish pronunciation is often less phonetic than spelling suggests, so listening to native audio is especially helpful.

A learner-friendly approximation might be:

• frygten ≈ FRÜG-ten or FRÜG-dn
• forsvinder ≈ for-SVIN-er

Those are only approximations, but they can help you get started.