Ég er alveg viss.

• Ég = the subject pronoun, I
• er = the present-tense form of vera (to be) used with ég
• alveg = an adverb that strengthens the statement, like completely, totally, or really
• viss = an adjective meaning sure/certain

So the structure is very straightforward: subject + verb + adverb + adjective.

Because er is the 1st person singular present tense form used with ég.

The verb vera (to be) is irregular, so its present-tense forms have to be learned individually:

• ég er = I am
• þú ert = you are
• hann/hún/það er = he/she/it is
• við erum = we are
• þið eruð = you are
• þeir/þær/þau eru = they are

So Ég er is simply the normal Icelandic equivalent of I am.

Here alveg works as an intensifier. It makes viss stronger.

Depending on context, alveg can mean things like:

• completely
• totally
• absolutely
• sometimes just really

In this sentence, it strengthens the idea of certainty. Without it, the sentence is still natural, just less emphatic.

Compare:

• Ég er viss. = I’m sure.
• Ég er alveg viss. = I’m absolutely/completely sure.

Yes, absolutely. Ég er viss is a complete and natural sentence.

Adding alveg just makes the statement stronger or more emphatic. So the difference is mainly one of tone:

• Ég er viss. = neutral
• Ég er alveg viss. = stronger, more emphatic

In Icelandic, adjectives often agree with the noun or pronoun they describe in gender, number, and case.

Here, viss is a predicate adjective after er. With ég, you might expect agreement to show up clearly, but in this particular case the nominative singular form viss is the same in the most relevant forms a learner is likely to meet here, so there is no obvious visible change in the sentence.

The important beginner point is:

• after vera, adjectives often describe the subject
• viss is the adjective doing that job here

Later, when you learn adjective inflection in more detail, you’ll see agreement more clearly with other adjectives and forms.

Not always.

Viss is often used with um when you say what you are sure about:

• Ég er viss um það. = I’m sure about that.
• Ég er viss um svarið. = I’m sure about the answer.

But if the context is already clear, Icelandic can simply say:

• Ég er viss.
• Ég er alveg viss.

So in your sentence, nothing is missing. It works perfectly well on its own.

Yes. This is the normal, basic Icelandic word order for a simple statement:

• Ég = subject
• er = verb
• alveg viss = complement

So this is a very standard sentence pattern.

A question version would change the order:

• Ertu alveg viss? = Are you absolutely sure?

That verb-first pattern is very common in Icelandic questions.

A rough learner-friendly guide would be:

• Ég ≈ yeg
• er ≈ ehr
• alveg ≈ AL-veg, though the final g is softer than an English g
• viss ≈ viss

A few useful notes:

• é in ég sounds like ye
• Icelandic r is usually trilled or tapped
• the g in alveg is not always pronounced like a hard English g
• ss in viss is voiceless, like English ss

If you want to sound natural, the rhythm matters too: Ég er alveg viss is usually said smoothly, with alveg unstressed compared to viss.

Yes, very common. It is a natural everyday way to emphasize certainty.

You will also hear related expressions such as:

• Ég er nokkuð viss. = I’m fairly sure.
• Ég er ekki viss. = I’m not sure.
• Ég er ekki alveg viss. = I’m not completely sure.

So alveg viss is a useful phrase pattern to remember.

You usually put ekki after the verb:

• Ég er ekki viss. = I’m not sure.
• Ég er ekki alveg viss. = I’m not completely sure.

That placement is very typical in Icelandic:

• subject + verb + ekki + rest

So if you know Ég er alveg viss, it is easy to build the negative form from it.

It is neutral and works in both formal and informal situations.

It is not slang, and it is not especially stiff or bookish either. It is simply a normal, everyday Icelandic sentence. That makes it a very useful pattern to learn early.