Advarselssignalet fra brandalarmen er højt.

Because Danish, like English, often makes compound nouns by joining words together. In this case:

• advarsel = warning
• signal = signal
• advarselssignal = warning signal
• advarselssignalet = the warning signal

So Danish prefers one combined noun where English might also sometimes use a noun phrase.

It is the definite ending, meaning the.

Danish usually adds the to the end of the noun instead of putting a separate word in front:

• et signal = a signal
• signalet = the signal

Since advarselssignal is a neuter noun, its definite form ends in -et.

That s is a linking s used in many Danish compounds.

So the structure is:

• advarsel
• s
• signal
• et

This linking s does not usually have a separate meaning. It just helps connect the parts of the compound. English has something similar in a few older forms, but Danish uses this type of linking much more often.

Brandalarmen means the fire alarm.

It is another compound:

• brand = fire
• alarm = alarm
• brandalarm = fire alarm
• brandalarmen = the fire alarm

The ending is -en because alarm is a common gender noun in Danish, not a neuter noun.

So:

• en alarm = an alarm
• alarmen = the alarm

Compare that with neuter nouns:

• et signal = a signal
• signalet = the signal

Fra means from.

So fra brandalarmen means from the fire alarm.

It shows the source of the warning signal. In English, this is very similar: the warning signal from the fire alarm.

Because the subject of the sentence is advarselssignalet, and that noun is neuter.

When an adjective is used after er and describes a neuter singular noun, it usually takes -t:

• Signalet er højt = The signal is loud
• Huset er stort = The house is big

With a common gender singular noun, you usually get the basic form:

• Alarmen er høj = The alarm is loud

So højt agrees with the neuter noun advarselssignalet.

Yes. Høj can mean high, tall, or loud, depending on context.

In this sentence, because we are talking about a sound signal, højt means loud.

Examples:

• Et højt tårn = a tall tower
• Et højt bjerg = a high mountain
• Musikken er høj = the music is loud

So the context tells you which meaning is intended.

This is the normal Danish order for a simple statement:

• subject: Advarselssignalet fra brandalarmen
• verb: er
• adjective/complement: højt

So it works like English:

• The warning signal from the fire alarm is loud

The phrase fra brandalarmen belongs to the subject noun phrase and tells you which warning signal we mean.

Yes, that is also possible.

• Advarselssignalet fra brandalarmen = the warning signal from the fire alarm
• Brandalarmens advarselssignal = the fire alarm’s warning signal

Both are natural, but they are built differently:

• fra-phrase = more like from the fire alarm
• -s genitive = more like the fire alarm’s

The version with fra may feel slightly clearer and less compact for learners.

The main thing to know is that compounds are usually pronounced as one unit, with the main stress usually earlier in the word.

A rough guide might be:

• advarselssignalet ≈ AH-thvar-sels-see-na-let
• brandalarmen ≈ BRAN-dah-lar-men
• højt has a rounded vowel somewhat like German ö, followed by a soft ending

A few useful pronunciation notes:

• d in advarsel is often very soft
• the double ss does not mean you pronounce two separate s sounds; it is just spelled that way because of the compound boundary
• ø is a vowel English does not really have, so it takes practice

Yes:

• Advarselssignalet = the warning signal
• fra = from
• brandalarmen = the fire alarm
• er = is
• højt = loud

So the full structure is:

• the warning signal
• from the fire alarm
• is loud

That makes it easier to see how the Danish sentence is built.