Mobilsignalet er svagt.

Because Danish, like German, very often forms compound nouns by joining words together.

• mobil = mobile phone / mobile
• signal = signal

So mobilsignal means mobile signal or cell signal.

When it becomes definite, Danish adds the definite ending to the whole noun, giving:

• et mobilsignal = a mobile signal
• mobilsignalet = the mobile signal

Writing it as two words would usually be incorrect in standard Danish.

The ending -et is the definite article suffix for many neuter nouns in Danish.

The base noun here is:

• et signal = a signal

Its definite form is:

• signalet = the signal

Since mobilsignal is also neuter, it follows the same pattern:

• et mobilsignal = a mobile signal
• mobilsignalet = the mobile signal

So Danish often puts the at the end of the noun instead of using a separate word before it.

You learn it from the dictionary form:

• et signal

In Danish, nouns are mainly either:

• common gender: take en
• neuter gender: take et

Since it is et signal, it is neuter. That matters because both the definite ending and the adjective form depend on it.

Because svag must agree with the noun it describes.

The adjective is:

• svag = weak

But with a singular neuter noun, it becomes:

• svagt

So:

• en forbindelse er svag = a connection is weak
• et signal er svagt = a signal is weak

Since mobilsignalet is built on et signal, the correct form is svagt.

Good question. Here, svagt is a predicative adjective, meaning it comes after er and describes the subject.

In Danish, predicative adjectives agree mainly with:

• gender
• number

They do not switch to the definite -e form just because the noun is definite.

So:

• et signal er svagt = a signal is weak
• signalet er svagt = the signal is weak

But when the adjective stands before a definite noun, you usually get -e:

• det svage signal = the weak signal

So:

• after er → svagt
• before a definite noun → svage

Er is the present tense of at være = to be.

So:

• er = is / are / am depending on context

In this sentence:

• Mobilsignalet er svagt.
• The mobile signal is weak.

It works just like English is here.

Yes, absolutely.

• Signalet er svagt = The signal is weak
• Mobilsignalet er svagt = The mobile signal is weak

Adding mobil- just makes it more specific. It tells you that it is the mobile/cell signal, not some other kind of signal.

A careful approximate pronunciation for an English speaker is:

• mobilsignalet ≈ mo-BEEL-seeg-na-let
• er ≈ a very short air or uh
• svagt ≈ something like svauwt / svagt, with a softened final sound depending on accent

A few useful notes:

• g can be softer than English learners expect.
• er is often unstressed and very quick in normal speech.
• Danish pronunciation is often less phonetic than spelling suggests, so listening to native audio is especially helpful.

Related, yes, but in Danish mobil often means mobile phone.

So in a compound like mobilsignal, mobil- means something like:

• mobile-phone
• cellular

That is why the whole sentence is usually understood as talking about cell phone reception.

Yes. Depending on context, English might translate it in slightly different natural ways:

• The mobile signal is weak
• The phone signal is weak
• The cell signal is weak
• There is poor reception

The Danish sentence is short and natural, and English may choose a more idiomatic wording depending on the situation.

Because Danish usually expresses definiteness by adding an ending to the noun:

• en bil = a car

• bilen = the car

• et signal = a signal
• signalet = the signal

So mobilsignalet already includes the meaning of the mobile signal. A separate the-word is not normally used here.

Yes, but in a normal neutral statement, Mobilsignalet er svagt is the standard order.

Danish main clauses follow the verb-second rule, so if you move another element to the front, the verb stays in second position:

• Mobilsignalet er svagt.
• Her er mobilsignalet svagt. = Here, the mobile signal is weak.
• I dag er mobilsignalet svagt. = Today, the mobile signal is weak.

So the basic sentence is simple, but the verb placement becomes important if you add extra information.

Sometimes, but it is not exactly the same.

• svagt = weak
• dårligt = bad / poor

So:

• Mobilsignalet er svagt focuses on signal strength
• Mobilsignalet er dårligt sounds more like the signal quality/reception is poor in a broader sense

Both can be understandable in context, but svagt is especially natural when talking about weak signal strength.

The indefinite version would be:

• Et mobilsignal er svagt. = A mobile signal is weak.

But in real-life usage, that sounds more general or less natural unless you are talking about some unspecified signal.

If you mean the actual signal where you are, Danish more naturally uses the definite form:

• Mobilsignalet er svagt. = The mobile signal is weak.

That is similar to how English often talks about the signal in a specific situation.