När hon hostar på bussen, håller hon handen framför munnen och näsan.

Because Swedish uses verb-second word order in main clauses.

The sentence starts with the subordinate clause När hon hostar på bussen (When she coughs on the bus). After that, the main clause begins, and in a Swedish main clause, the finite verb usually comes in the second position.

So:

• När hon hostar på bussen, håller hon handen framför munnen och näsan.

Literally, the structure is:

• When she coughs on the bus, holds she her hand in front of the mouth and the nose.

That sounds strange in English, but it is normal in Swedish.

If you started directly with the main clause, you would say:

• Hon håller handen framför munnen och näsan.

But once another element comes first, like När hon hostar på bussen, the verb moves before the subject:

• ..., håller hon ...

När means when.

In this sentence, it introduces a time clause:

• När hon hostar på bussen = When she coughs on the bus

A learner might compare it with om, which often means if. The difference is:

• när = when / whenever
• om = if

So this sentence describes something that happens at the time she coughs, not a condition or uncertainty.

Swedish often uses the present tense for general habits, repeated actions, and things that happen whenever a situation occurs.

So:

• När hon hostar på bussen does not have to mean only right now.
• It can mean when(ever) she coughs on the bus.

That is very similar to English, where we also say:

• When she coughs, she covers her mouth.

So the present tense here is completely natural.

In Swedish, public transport is often expressed with på rather than i.

So you commonly say:

• på bussen = on the bus
• på tåget = on the train
• på tunnelbanan = on the subway

Even though English also says on the bus, this can still confuse learners because Swedish sometimes uses i where English uses in, but with transport, på is very common.

So:

• När hon hostar på bussen = When she coughs on the bus

This is a very common feature of Swedish.

When talking about body parts or things closely connected to a person, Swedish often uses the definite form instead of a possessive word like her.

So instead of saying:

• sin hand
• sin mun
• sin näsa

Swedish very naturally says:

• handen = the hand
• munnen = the mouth
• näsan = the nose

Even though English usually says her hand, her mouth, her nose, Swedish often prefers the definite form when it is already obvious whose body parts are meant.

So:

• hon håller handen framför munnen och näsan

literally looks like:

• she holds the hand in front of the mouth and the nose

but the natural English meaning is:

• she holds her hand in front of her mouth and nose

Yes, you could, but it would sound less natural in this context.

Swedish often avoids possessives with body parts when the owner is obvious. So:

• hon håller handen framför munnen och näsan

is the most natural everyday phrasing.

If you said:

• hon håller sin hand framför sin mun och sin näsa

it would sound heavier and more explicit than necessary.

So the version with the definite forms is preferred.

Because the second part is a main clause, and it needs its own subject.

The sentence has two parts:

1. När hon hostar på bussen — subordinate clause
2. håller hon handen framför munnen och näsan — main clause

Even though hon already appears in the first clause, Swedish still needs the subject in the main clause as well.

So you cannot leave it out here.

Framför means in front of.

So:

• framför munnen och näsan = in front of the mouth and nose

In this context, it describes where she places her hand.

It does not mean before in the time sense here. It is about physical position.

Because each noun refers to a specific body part: the mouth and the nose.

In Swedish, when listing body parts like this, it is normal to keep each noun in the definite form:

• munnen och näsan

This is just the natural way to say the mouth and the nose, which English then often translates more naturally as her mouth and nose in context.

The comma is possible and helpful, but in modern Swedish it is often optional in this kind of sentence.

So both of these can be seen:

• När hon hostar på bussen, håller hon handen framför munnen och näsan.
• När hon hostar på bussen håller hon handen framför munnen och näsan.

The comma can make the sentence easier to read by clearly separating the subordinate clause from the main clause, but many Swedish sentences like this are written without one.

The infinitives are:

• hosta = to cough
• hålla = to hold

Here they appear in the present tense:

• hostar = coughs / is coughing
• håller = holds / is holding

A useful pattern to notice:

• hosta → hostar
• hålla → håller

So this sentence gives you two common present-tense verb forms.

It can most naturally describe a general or repeated behavior.

• När hon hostar på bussen, håller hon handen framför munnen och näsan.

This usually sounds like:

• Whenever she coughs on the bus, she puts her hand in front of her mouth and nose.

So it suggests a habit or normal action, not necessarily one single moment only.

Because Swedish, like English, normally does not repeat the preposition when one preposition clearly applies to both nouns.

So:

• framför munnen och näsan

naturally means:

• in front of the mouth and nose

This is shorter and completely normal. Repeating framför would sound unnecessarily heavy unless you wanted special emphasis.