Hvis mit håndled gør ondt, smører jeg salve på det.

Hvis means if.

In this sentence, Hvis mit håndled gør ondt is a condition clause: If my wrist hurts.

A few useful comparisons:

• hvis = if
• når = often when, especially for things that regularly happen or are expected to happen

So:

• Hvis mit håndled gør ondt, ... = If my wrist hurts, ...
• Når mit håndled gør ondt, ... can sound more like When my wrist hurts / Whenever my wrist hurts...

Both can sometimes be possible, but hvis clearly presents it as a condition.

Because håndled is a neuter noun in Danish.

Danish has two grammatical genders for nouns:

• common gender → takes en, min, den
• neuter gender → takes et, mit, det

So:

• en arm → min arm
• et håndled → mit håndled

That is why the sentence uses mit.

For the same reason: håndled is a neuter noun.

Since håndled is et håndled, the pronoun referring back to it is det.

So:

• en stol → den
• et bord → det
• et håndled → det

In the sentence:

• smører jeg salve på det = I apply ointment to it

Here det refers back to mit håndled.

Gør ondt is a fixed expression meaning hurts or is painful.

Literally, it is something like does hurt/pain, but you should learn it as a whole expression.

Examples:

• Det gør ondt. = It hurts.
• Min ryg gør ondt. = My back hurts.
• Mit håndled gør ondt. = My wrist hurts.

English often uses a single verb, hurt, but Danish commonly uses this expression instead.

Because Danish main clauses usually follow the verb-second rule.

The sentence begins with a subordinate clause:

• Hvis mit håndled gør ondt,

After that, the main clause comes, and in a Danish main clause the finite verb usually comes in the second position:

• smører jeg salve på det

So the structure is:

• Hvis ... , smører jeg ...

not

• Hvis ... , jeg smører ...

This is very common in Danish:

• Når jeg kommer hjem, spiser jeg.
• Hvis det regner, bliver vi inde.
• Efter arbejde går hun hjem.

Because Danish commonly says smøre noget på noget for apply/spread something on something.

So:

• smøre salve på det = apply ointment to it / put ointment on it

The preposition på literally means on, and that matches the idea of spreading something onto a surface or body part.

Other examples:

• Han smører smør på brødet. = He spreads butter on the bread.
• Hun smører creme på hænderne. = She puts cream on her hands.

Yes, you could.

• Hvis mit håndled gør ondt, smører jeg salve på det.
• Hvis mit håndled gør ondt, smører jeg salve på håndleddet.

Both are correct.

The version with det sounds natural because Danish, like English, often uses a pronoun once the noun has already been mentioned.

Compare:

• My wrist hurts, so I put ointment on it.
• not usually ...on the wrist unless you want to repeat it for emphasis or clarity

So på det is normal and efficient.

Because Danish often uses the present tense for general habits, repeated actions, and real conditions.

This sentence means something like:

• If my wrist hurts, I apply ointment to it
• Whenever my wrist hurts, I put ointment on it

It describes what the speaker generally does in that situation.

This is similar to English, which also often uses the present tense in conditional sentences:

• If it rains, I stay inside.
• If my wrist hurts, I put ointment on it.

Because salve here is being used in a fairly general, uncountable way: ointment rather than an ointment.

So:

• smører jeg salve på det = I apply ointment to it

If you wanted to refer to a specific ointment or a single container/tube in context, Danish might use something more specific, depending on what you mean.

But in a general sentence about treatment, bare salve is very natural.

Yes.

Håndled is a compound noun:

• hånd = hand
• led = joint

Together, håndled means wrist.

Danish forms many nouns this way, and they are usually written as one word, unlike English, which sometimes uses separate words.

This is very common in Danish, so it is worth getting used to compound nouns early.

Yes, but the structure changes.

Two common patterns are:

• Mit håndled gør ondt. = My wrist hurts.
• Jeg har ondt i håndleddet. = I have pain in my wrist / My wrist hurts.

So you could say:

• Hvis mit håndled gør ondt, smører jeg salve på det.
• Hvis jeg har ondt i håndleddet, smører jeg salve på det.

Both are natural, but they are built differently:

• body part + gør ondt
• person + har ondt i + body part

That is a very useful pattern to learn for talking about pain in Danish.