Bygningsfejl, nærsynethed og langsynethed kræver forskellige brillestyrker.

Possibly not.

In ordinary Danish, bygningsfejl means something like building defect or construction flaw:

• bygning = building
• fejl = fault, error, defect

So in a sentence about eyesight and glasses, many learners would expect brydningsfejl instead, which means refractive error.

So if this sentence is about vision, bygningsfejl is very likely a typo for brydningsfejl.

Because Danish often leaves out articles when talking about things in a general, category-level way.

Here the sentence lists conditions in general:

• bygningsfejl
• nærsynethed
• langsynethed

This is similar to English sentences like:

• Myopia and hyperopia require different lens strengths.
• Cats and dogs need different food.

You are not talking about one specific case of each; you are talking about the conditions as general concepts.

Because Danish verbs do not change form depending on whether the subject is singular or plural.

So:

• Jeg kræver = I require
• Han kræver = he requires
• De kræver = they require

The present tense form stays kræver.

That is different from English, where you get:

• it requires
• they require

In Danish, there is no such change.

Because forskellige is the plural form of the adjective.

It describes brillestyrker, which is plural:

• en forskellig styrke = a different strength
• forskellige styrker = different strengths

So the -e ending is there because the noun is plural.

This is very common in Danish adjectives:

• en stor bil = a big car
• store biler = big cars

It is a compound noun:

• brille = glasses
• styrke = strength, power

So brillestyrke means something like glasses strength or lens power/prescription strength.

The form in the sentence, brillestyrker, is plural:

• en brillestyrke = one lens strength / one prescription strength
• flere brillestyrker = several lens strengths / different prescription strengths

A useful thing to notice: Danish very often builds new words by joining nouns together into one word.

Because in Danish compounds, the first noun is usually in a basic stem form, not necessarily the plural form you might expect from English.

So:

• brille
  • styrke → brillestyrke

This is normal in Danish compounding. English learners often want to keep the full plural, but Danish usually does not do that.

Compare the general pattern:

• skolebog = school book
• børnehaveklasse = kindergarten class
• bilmotor = car engine

The first part acts more like a classifier than a full separate noun.

They are both built from smaller parts.

nærsynethed

• nær = near
• synet relates to seeing/sighted
• -hed = -ness as a noun ending

So it literally means something like near-sightedness.

langsynethed

• lang = far/long
• synet = sighted
• -hed = -ness

So it literally means far-sightedness.

The ending -hed is very common in Danish and works a lot like English -ness:

• fri = free → frihed = freedom
• sikker = safe/certain → sikkerhed = safety/security
• nærsynet = near-sighted → nærsynethed = near-sightedness

Grammatically, fejl is one of those Danish nouns whose singular and plural can look the same in the indefinite form.

• en fejl = an error
• flere fejl = several errors

So bygningsfejl could in principle be understood as singular or plural depending on context.

In this sentence, it is most natural to read it as a general category noun in a list, not as one specific defect.

If the intended word was really brydningsfejl, the same point still applies: it can function as a general term for a type of visual defect.

Because this is a simple list:

• Bygningsfejl, nærsynethed og langsynethed

Danish normally uses commas between items in a list, but not before og in a simple series.

So this is just like English:

• A, B and C

rather than:

• A, B, and C

The so-called Oxford comma is much less standard in Danish.

It is the normal Danish main-clause order:

Subject + verb + object

• Bygningsfejl, nærsynethed og langsynethed = subject
• kræver = verb
• forskellige brillestyrker = object

So the sentence structure is very straightforward.

You can also think of it as following the usual Danish V2 pattern: in a main clause, the finite verb comes in the second position. Here, the entire subject phrase fills the first position, and kræver comes next.

A rough English-friendly guide would be:

• Bygningsfejl ≈ BYNG-nings-file
• nærsynethed ≈ NAIR-soo-net-hed
• langsynethed ≈ LANG-soo-net-hed
• kræver ≈ KREH-ver
• forskellige ≈ FOR-skel-ee
• brillestyrker ≈ BRIL-leh-stur-ger

A few cautions:

• Danish y is not like English y; it is a front rounded vowel.
• æ is a very important Danish vowel, somewhat like the vowel in air for many learners, though not exactly.
• Final syllables are often weaker and less clearly pronounced than English learners expect.

If you want to sound natural, the rhythm matters just as much as the individual sounds.

Yes. A very literal translation would sound stiff.

A more natural English rendering would be something like:

• Refractive errors, myopia, and hyperopia require different prescription strengths.
• Nearsightedness and farsightedness require different glasses prescriptions.

Exactly which English version is best depends on whether bygningsfejl is really intended, or whether it should be brydningsfejl. If it is a typo, then the sentence is clearly about visual/refractive problems and glasses prescriptions.