Stolen støtter ryggen.

In Danish, the definite article is very often added to the end of the noun instead of standing as a separate word.

• stol = chair
• stolen = the chair

Here, stol is a common-gender noun, so the definite ending is -en.

A separate word like den is usually used when there is an adjective or when you want extra emphasis:

• stolen = the chair
• den gamle stol = the old chair
• den stol can mean that chair or a specially emphasized the chair

Danish often uses the definite form with body parts when the owner is obvious from the context.

So:

• ryggen literally = the back
• in natural English, that may correspond to your back or the back, depending on context

That means Stolen støtter ryggen is idiomatic Danish for something like The chair supports your back / the back.

You can say din ryg, but that sounds more explicit or contrastive:

• Stolen støtter ryggen = neutral, natural
• Stolen støtter din ryg = more explicit, maybe contrastive

støtter is the present tense of the verb at støtte.

• at støtte = to support
• støtter = support / supports

So the sentence is in the present tense.

A useful pattern:

• jeg støtter = I support
• du støtter = you support
• han/hun støtter = he/she supports
• stolen støtter = the chair supports

Because Danish verbs are much simpler than English verbs in this area. In the present tense, the verb form stays the same regardless of the subject.

So Danish uses støtter with:

• jeg = I
• du = you
• han/hun = he/she
• vi = we
• de = they

English changes between I support and it supports, but Danish does not make that distinction here.

This sentence has the basic word order:

subject + verb + object

• Stolen = subject
• støtter = verb
• ryggen = object

So the structure is straightforward.

If you reverse the nouns, you change the meaning:

• Stolen støtter ryggen = the chair supports the back
• Ryggen støtter stolen = the back supports the chair

Danish usually relies on word order a lot, since nouns do not normally show case endings the way they do in some other languages.

The tricky letters here are ø and y.

• ø in støtter is roughly like German ö or the vowel in French deux
• y in ryggen is roughly like German ü or French u

A practical trick:

• for ø: round your lips as if saying o, but try to say e
• for y: round your lips as if saying oo, but try to say ee

Also, Danish pronunciation is often softer than the spelling suggests, so the sentence may sound less sharply articulated than an English speaker expects.

Yes, at støtte can be used both literally and figuratively.

It can mean physical support:

• Stolen støtter ryggen = the chair supports the back

But it can also mean emotional, practical, financial, or political support:

• Jeg støtter dig = I support you
• De støtter projektet = they support the project
• Hun støtter partiet = she supports the party

So it is a very general verb, just like English support.

Yes, it is understandable and natural enough, especially in a descriptive or instructional context.

That said, in everyday speech Danes might also say things like:

• Stolen giver god støtte til ryggen = the chair gives good support to the back
• Denne stol støtter ryggen godt = this chair supports the back well

These versions can sound a bit more idiomatic when talking about comfort or ergonomics. But Stolen støtter ryggen is still a perfectly useful learner sentence and grammatically fine.