Flutningabíllinn er tilbúinn fyrir flutninginn.

Because Icelandic very often makes compound nouns by joining words together.

Here, flutningabíllinn is built like this:

• flutninga- = moving / transport
• bíll = car, truck
• -inn = the

So flutningabíllinn is literally something like the moving-truck.

A useful rule: in Icelandic compounds, the last part is the main noun. That means bíll determines things like gender and most of the inflection pattern.

It is the suffixed definite article, meaning the.

So:

• flutningabíll = a moving truck
• flutningabíllinn = the moving truck

Unlike English, Icelandic often puts the at the end of the noun instead of using a separate word.

The same thing happens in flutninginn:

• flutningur = a move / transport
• flutninginn = the move

Er is the 3rd person singular present tense of vera, the verb to be.

So:

• ég er = I am
• þú ert = you are
• hann / hún / það er = he / she / it is

Since flutningabíllinn is a singular subject, Icelandic uses er:

• Flutningabíllinn er ... = The moving truck is ...

If the subject were plural, you would use eru instead:

• Flutningabílarnir eru tilbúnir ... = The moving trucks are ready ...

Because tilbúinn must agree with the subject, flutningabíllinn.

The noun flutningabíll is:

• masculine
• singular
• here in the nominative

So the adjective also appears in the masculine singular nominative form:

• tilbúinn

Compare:

• masculine singular: tilbúinn
• feminine singular: tilbúin
• neuter singular: tilbúið
• masculine plural: tilbúnir

This is a very important feature of Icelandic: adjectives usually agree with the noun they describe.

Because the final part of the compound is bíll, and bíll is a masculine noun.

In Icelandic compounds, the last element usually decides the gender of the whole word.

So:

• bíll = masculine
• therefore flutningabíll = masculine

That is also why the adjective is tilbúinn rather than a feminine or neuter form.

Here, flutninginn is in the accusative singular definite.

The preposition fyrir can take different cases in different uses, but in this expression you should learn it as:

• tilbúinn fyrir + accusative = ready for + something

So:

• fyrir flutning = for a move
• fyrir flutninginn = for the move

A practical learner tip: it is often easiest to memorize this as a chunk:

• vera tilbúinn fyrir eitthvað = to be ready for something

Because the sentence is talking about a specific truck and a specific move, not just moving trucks and moves in general.

So:

• Flutningabíllinn = the moving truck
• flutninginn = the move

This is perfectly normal in Icelandic. English sometimes uses fewer definite forms in similar situations, but Icelandic often marks both nouns as definite when both are specific and known from context.

Yes. This is a very normal Icelandic main-clause word order:

• Flutningabíllinn = subject
• er = verb
• tilbúinn = predicative adjective
• fyrir flutninginn = prepositional phrase

So the pattern is basically:

• Subject + Verb + Complement

That is very similar to English here:

• The moving truck is ready for the move.

One thing to remember is that Icelandic is often described as a verb-second language. In a basic sentence like this, the subject comes first, so the verb naturally appears second.

The dictionary forms are:

• flutningabíll = moving truck
• vera = to be
• tilbúinn = ready
• fyrir = for
• flutningur = move, transport

The actual forms in the sentence are inflected:

• flutningabíllinn = definite singular form of flutningabíll
• er = present tense of vera
• flutninginn = accusative singular definite of flutningur

Looking up the dictionary forms is very helpful, because Icelandic words often appear in sentences in forms that look quite different from the base form.

You would remove the definite endings:

• Flutningabíll er tilbúinn fyrir flutning.

That means:

• A moving truck is ready for a move or
• The moving truck is ready for moving, depending on context

The key contrast is:

• flutningabíll = a moving truck
• flutningabíllinn = the moving truck
• flutning = a move
• flutninginn = the move

So the endings are doing the job that English often does with a and the.