Når telefonen ringer, rejser hun sig fra sofaen.

Når usually means when in the sense of whenever or at the time that.

In this sentence, Når telefonen ringer means When the phone rings or Whenever the phone rings.

A learner often compares når with da:

• når = for repeated situations, general truths, or future time
• da = for a specific event in the past

So here, når is natural because this sounds like a repeated or general situation: every time the phone rings, she gets up.

Telefonen means the phone.

In Danish, the definite article is often added to the end of the noun:

• en telefon = a phone
• telefonen = the phone

The same thing happens with sofaen:

• en sofa = a sofa
• sofaen = the sofa

This is very common in Danish and is one of the first big differences from English.

Because the sentence uses the present tense.

• at ringe = to ring

• ringer = rings / is ringing

• at rejse sig = to get up / rise
• rejser sig = gets up / is getting up

In Danish, the present tense is usually formed by adding -r to the infinitive:

• ringe → ringer
• rejse → rejser

This is because of Danish word order, especially the verb-second rule.

The sentence begins with the clause Når telefonen ringer. After that opening clause, the main clause must put the finite verb first:

• Når telefonen ringer, rejser hun sig fra sofaen.

Not:

• Når telefonen ringer, hun rejser sig fra sofaen.

So the structure is:

• subordinate clause
• then in the main clause: verb + subject

This inversion is very normal in Danish.

Sig is a reflexive pronoun. Here it is part of the verb expression rejse sig, which means to get up, to stand up, or to rise.

Compare:

• hun rejser = she travels
• hun rejser sig = she gets up

So sig is very important here. Without it, the meaning changes a lot.

Because the subject is hun, the reflexive form is sig.

Not exactly.

• rejse sig = get up / stand up / rise from a sitting or lying position
• stå op = get up in the sense of get out of bed

In this sentence, she is getting up from the sofa, so rejse sig is the right choice.

Fra means from.

So:

• fra sofaen = from the sofa

It shows the place she is moving away from. Since she is getting up from where she was sitting, fra is exactly the natural preposition here.

Most naturally, it describes a habitual or general situation:

• Whenever the phone rings, she gets up from the sofa.

That is because når often suggests something that happens regularly or generally.

However, Danish present tense can also sometimes refer to the future depending on context. So in the right situation, it could also mean something like:

• When the phone rings, she gets up from the sofa.

But without more context, a habitual reading is the most likely.

The most natural translations are:

• she gets up from the sofa
• she stands up from the sofa
• she rises from the sofa

The most everyday English version is probably she gets up from the sofa.

Rise from the sofa is correct, but sounds more formal or literary in English.

A rough English-friendly guide could be:

Nåhr telephone-n RING-er, RYE-ser hoon sye fra SO-fa-en

A few useful notes:

• når has a vowel sound that does not match English perfectly
• ringer has a soft Danish r
• rejser begins with a sound somewhat like rye-
• sig is often pronounced more like sigh than it looks
• hun sounds roughly like hoon
• sofaen is pronounced something like SO-fa-en, with the ending clearly separate

Pronunciation varies a bit by speaker and region, but those approximations can help you get started.

Yes:

Hun rejser sig fra sofaen, når telefonen ringer.

That means the same thing.

The difference is mostly one of focus and style:

• Når telefonen ringer, rejser hun sig fra sofaen. puts the time condition first
• Hun rejser sig fra sofaen, når telefonen ringer. starts with what she does

Both are correct Danish.