Stoffet i hendes kjole føles let, og stoffet i min jakke føles varmt.

Here stof means fabric or material.

Danish stof is a broad word and can mean:

• fabric/material
• substance
• sometimes drugs in other contexts

In this sentence, because we are talking about a dress and a jacket, the meaning is clearly fabric.

Because stoffet is the definite singular form: the fabric.

• et stof = a fabric / a material
• stoffet = the fabric

The noun stof is a neuter noun, so the definite ending is -et.
The spelling changes to stoffet with double f, which is just the normal written form.

I means in.

So:

• stoffet i hendes kjole = the fabric in her dress
• stoffet i min jakke = the fabric in my jacket

English might sometimes say the fabric of her dress, but Danish very naturally uses i here.

This is a very common Danish question.

Sin/sit/sine is used when the possessor refers back to the subject of the clause.
Here, the subject is stoffet, not hun.

So:

• stoffet i hendes kjole = the fabric in her dress

If you used sin, it would try to refer back to stoffet, which does not make sense here.

A helpful comparison:

• Hun tager sin kjole på. = She puts on her dress.
  Here sin refers back to hun.
• Stoffet i hendes kjole... = The fabric in her dress...
  Here the subject is stoffet, so hendes is correct.

Because Danish, like English, normally does not use an article with a possessive.

• min jakke = my jacket
• not den min jakke

The possessive already makes the noun definite enough.

Føles means feels.

It is used for how something seems to the touch or in sensation:

• Stoffet føles let. = The fabric feels light.
• Stoffet føles varmt. = The fabric feels warm.

It is slightly different from er:

• er let/varmt = is light/warm
• føles let/varmt = feels light/warm

So føles focuses on perception or sensation.

Because adjectives in Danish often agree with a neuter singular noun like stoffet.

With a neuter singular noun, many adjectives take -t:

• varm → varmt

So:

• stoffet ... føles varmt

But let is already the correct form here, so it does not become lett.

In other words:

• varm changes to varmt
• let stays let

No. Here let means light in the sense of not heavy or possibly light/airy in feel.

Danish let can mean different things depending on context:

• easy
• light in weight
• sometimes light in intensity or style

Because the sentence is about fabric, the meaning is light rather than easy.

Because varmt agrees with stoffet, not with jakke.

The subject of the clause is:

• stoffet i min jakke

The head noun there is stoffet, which is neuter.
So the adjective agrees with stoffet, not with jakke.

That is why we get:

• stoffet ... føles varmt

Danish often repeats the noun to keep the sentence clear and balanced.

So this structure is very natural:

• Stoffet i hendes kjole føles let, og stoffet i min jakke føles varmt.

You could sometimes rephrase to avoid repetition, but the repeated noun makes the contrast very clear:

• her dress vs my jacket
• light vs warm

No, it is normal main-clause word order.

Both parts follow the same pattern:

• Stoffet = subject
• føles = verb
• let/varmt = adjective complement

So after og, Danish simply starts a new coordinated clause:

• ..., og stoffet i min jakke føles varmt.

There is no inversion here because nothing has been moved to the front of the clause.

No. Hendes does not change to match the noun.

It stays hendes whether the noun is:

• singular or plural
• common gender or neuter

So:

• hendes kjole
• hendes hus
• hendes sko

The form depends on the owner being her, not on the grammatical gender of the thing owned.