Kennarinn segir að frumlagið sé ekki alltaf fyrst í setningunni.

Kennarinn means the teacher, while kennari means a teacher or just teacher in a general sense.

Icelandic usually adds the definite article to the end of the noun rather than using a separate word like English the.

• kennari = teacher
• kennarinn = the teacher

In this sentence, we are talking about a specific teacher, so kennarinn is used.

Here, að means that and introduces a subordinate clause:

• Kennarinn segir = The teacher says
• að frumlagið sé ekki alltaf fyrst í setningunni = that the subject is not always first in the sentence

This is different from another very common að, which can mark the infinitive, like að lesa = to read.
So in Icelandic, að can have more than one job. In this sentence, it is a conjunction meaning that.

For the same reason as kennarinn: the ending shows definiteness.

• frumlag = subject
• frumlagið = the subject

The sentence is talking about the subject as a grammatical concept, not just a subject.

The ending -ið is the definite article here.

Sé is the subjunctive form of vera (to be).
The indicative form would be er.

• er = is
• sé = be / is (subjunctive)

In Icelandic, the subjunctive is often used in subordinate clauses after verbs like segja (say), especially when reporting what someone says, thinks, claims, or believes.

So:

• Kennarinn segir að frumlagið er... may be heard in everyday speech in some contexts
• Kennarinn segir að frumlagið sé... is the more standard grammatical form here

For a learner, the main thing to remember is that after segir að, Icelandic often uses the subjunctive.

Sé is the present subjunctive, 3rd person singular form of vera (to be).

It matches frumlagið, which is singular:

• frumlagið = the subject
• sé = be / is (subjunctive singular)

So the clause literally works like:

• að frumlagið sé... = that the subject be / is...

In natural English, you would simply translate it as that the subject is...

In Icelandic, ekki (not) usually comes before the word or phrase it negates.

Here the idea is:

• ekki alltaf = not always

So:

• sé ekki alltaf fyrst = is not always first

This is very similar to English word order in this case.

If you changed the order, the emphasis could sound odd or unnatural. Ekki alltaf is the normal and expected sequence.

Here fyrst means first, and it functions adverbially.

It describes position in the sentence:

• fyrst í setningunni = first in the sentence

It is not describing a noun directly, so you can think of it as an adverb here rather than an adjective.

The idea is that the subject is not always in the first position.

Because í can take either the dative or the accusative, depending on meaning:

• í + dative = location, in
• í + accusative = motion into, into

Here the meaning is location:

• í setningunni = in the sentence

So Icelandic uses the dative.

Compare:

• í setningunni = in the sentence
• fara í setninguna would imply movement into something, which does not fit here

The base form is setning = sentence.

Then Icelandic adds both:

1. the definite article, and
2. the case ending

So:

• setning = sentence
• setningin = the sentence
• setningunni = in the sentence / to the sentence, depending on context

In this sentence, setningunni is dative singular definite because it follows í in a location meaning.

Good question. The sentence is making a general statement about Icelandic sentence structure, not demonstrating every possible word-order pattern inside this very clause.

In the subordinate clause:

• að frumlagið sé ekki alltaf fyrst í setningunni

the subject frumlagið does come before the verb sé, which is a normal default order.

But the meaning is that in Icelandic, the grammatical subject is not always the first element in a sentence. For example, some other element can come first for emphasis or because of normal word-order rules.

So the sentence is saying:

• sometimes the subject is first
• sometimes something else comes first

It is describing a rule, not necessarily showing the unusual pattern itself.

Yes. Frumlag is the standard Icelandic grammar term for the subject of a clause or sentence.

So if you are studying grammar:

• frumlag = subject
• sögn = verb
• andlag = object

In this sentence, frumlagið means the subject in the grammatical sense, not the topic of conversation in a general everyday sense.

Yes:

• Kennarinn = the teacher
• segir = says
• að = that
• frumlagið = the subject
• sé = is / be (subjunctive of vera)
• ekki = not
• alltaf = always
• fyrst = first
• í = in
• setningunni = the sentence

So the structure is:

• Kennarinn segir = The teacher says
• að frumlagið sé ekki alltaf fyrst í setningunni = that the subject is not always first in the sentence

Yes.

The sentence has two parts:

1. Main clause
   Kennarinn segir = The teacher says

2. Subordinate clause introduced by að
   að frumlagið sé ekki alltaf fyrst í setningunni = that the subject is not always first in the sentence

This is a very common pattern in Icelandic:

• X segir að... = X says that...
• Ég held að... = I think that...
• Hún veit að... = She knows that...

Recognizing að as the start of a subordinate clause is very useful for reading Icelandic sentences.