Han har ondt i skulderen efter arbejdet.

Because have ondt is a very common Danish way to say that someone is in pain.

So:

• Han har ondt = he is in pain / he hurts
• Jeg har ondt i ryggen = my back hurts
• Hun har ondt i hovedet = she has a headache / her head hurts

English often uses hurt, ache, or be sore, but Danish very often uses have + ondt.

Here, ondt means pain, hurting, or sore.

It comes from ond, which can mean painful in some contexts. In modern Danish, though, learners often first meet ond meaning evil or mean, so this can look confusing.

In the fixed expressions:

• have ondt = be in pain
• gøre ondt = hurt

ondt does not mean evil here. It only refers to pain.

With pain in a body part, Danish usually uses i.

So you say:

• ondt i skulderen = pain in the shoulder
• ondt i benet = pain in the leg
• ondt i ryggen = pain in the back

Using på skulderen would usually sound more like something is physically on the shoulder, or affecting the surface of it, not the normal way to talk about bodily pain.

Danish often uses the definite form for body parts when it is already obvious whose body part it is.

So:

• Han har ondt i skulderen literally looks like He has pain in the shoulder
• but in natural English it means His shoulder hurts

This is very normal in Danish. You often do not need a possessive like his, my, or her when the owner is clear from the subject.

Compare:

• Jeg har ondt i hånden = my hand hurts
• Hun har ondt i nakken = her neck hurts

Usually not in this exact pattern.

The natural phrase is:

• have ondt i skulderen

Using sin skulder here would sound much less idiomatic. Danish strongly prefers the body-part pattern with the definite form in expressions like this.

So a learner should treat have ondt i + definite body part as a standard structure.

Because the sentence is talking about one shoulder.

If both shoulders hurt, you would use the plural:

• Han har ondt i skuldrene = his shoulders hurt

So singular vs. plural here works the way you would expect.

It means after work or after the work.

In this sentence, it is most naturally understood as a time expression:

• his shoulder hurts after he has been working
• or after the workday

It can also suggest that the work is probably the reason, but grammatically efter arbejdet mainly tells you when.

If you wanted to make the cause more explicit, Danish could use something like:

• på grund af arbejdet = because of the work

Here arbejdet is the definite form: the work.

In Danish, the definite form is often used when the speaker means a specific, understood thing, such as:

• the work he has just done
• the workday
• the job in question

So efter arbejdet can be understood as after the work / after the workday.

In some contexts, Danish speakers may also say efter arbejde in a more general after work sense, but efter arbejdet is completely natural and points more clearly to a specific, understood period of work.

The sentence follows normal Danish main-clause word order:

• Han = subject
• har = finite verb
• ondt i skulderen = the rest of the predicate
• efter arbejdet = time expression

So:

• Han har ondt i skulderen efter arbejdet.

If you move the time expression to the front, Danish still keeps the verb in second position:

• Efter arbejdet har han ondt i skulderen.

That is a good example of the Danish V2 rule.

Yes. That is also natural Danish.

There is a slight difference in focus:

• Han har ondt i skulderen = focuses on him having pain
• Hans skulder gør ondt = focuses on the shoulder as the thing that hurts

Both are correct and common.

It can mean either, depending on context.

Danish present tense can describe:

• something happening right now
• something that usually happens
• a general situation

So Han har ondt i skulderen efter arbejdet could mean:

• right now, after work, his shoulder hurts
• or, more generally, his shoulder tends to hurt after work

Context tells you which meaning is intended.

It is structurally closer to he has pain in his shoulder, but in natural English the best translation is often simply his shoulder hurts.

That is a useful thing to remember with Danish:

• Danish form: have ondt i + body part
• natural English meaning: that body part hurts

So you should understand the Danish pattern as idiomatic, not translate it too mechanically word for word.