Learn Hardcore Icelandic: Stundum er ég einmana þegar ég borða einn.

The most natural are usually the first two. Putting stundum at the very beginning (as in the original) emphasizes “Sometimes…” as a starting point, similar to English.

Why is it er ég and not ég er right after stundum?

Icelandic main clauses normally follow a V2 word order (verb-second), similar to German:

Some element (subject, adverb, etc.)
Finite verb
Subject (if it wasn't in position 1)

So with stundum in first position, the finite verb er (“am”) must come second:

Stundum er ég einmana…
- 1: Stundum
- 2: er (verb)
- 3: ég (subject)

If the subject is first, then the subject comes before the verb:

Ég er stundum einmana…

Both are correct; the choice depends on what you want to emphasize.

What does einmana mean exactly, and is it an adjective like in English?

Einmana means “lonely”.

Grammatically, it behaves like an adjective but is indeclinable: it does not change form for gender, number, or case. You use einmana for:

Ég er einmana. – I am lonely.
Hún er einmana. – She is lonely.
Þau eru einmana. – They are lonely.

Unlike a normal adjective (e.g. ein / einn / eitt for “one/alone”), einmana always stays the same. It only appears in predicate position (after “to be”), not in front of nouns.

What is the difference between einmana and einn / ein / eitt?

They are related but different:

einmana = lonely (emotional state)
- Ég er einmana. – I am lonely.
einn / ein / eitt = one / alone (numeral or adjective, changes with gender)
- Ég borða einn. – I eat alone / I eat one (masculine object).
- Ég er einn. – I am alone. (speaker masculine)
- Ég er ein. – I am alone. (speaker feminine)

In the sentence:

Stundum er ég einmana – emotional loneliness: “Sometimes I feel lonely”.
þegar ég borða einn – physically alone while eating: “when I eat alone”.

So the sentence contrasts emotional loneliness (einmana) with being physically by oneself (einn).

Why is it einn at the end and not ein or eitt?

Einn / ein / eitt is the word “one/alone,” and it agrees with the grammatical gender and case of the subject (here ég).

If the speaker is grammatically masculine:
- Ég borða einn. – I eat alone.
If the speaker is grammatically feminine:
- Ég borða ein. – I eat alone.

So in a textbook or generic example, einn is often used by default (masculine form), but a female speaker would naturally say Ég borða ein.

Eitt would be neuter and is not used here for a person.

Could ég borða einn also mean “I eat one (of something)”?

Yes, context can make ég borða einn ambiguous:

“I eat alone”
- Here einn agrees with the subject (masculine), and means “by myself / alone”.
“I eat one (masculine thing)”
- Here einn agrees with an implied masculine object:
  - Ég borða einn (ís). – I’ll eat one (ice cream).
  - Ég borða einn (hamborgara). – I’ll eat one (hamburger).

In the sentence þegar ég borða einn after “I feel lonely”, the natural reading is “when I eat alone”, not “when I eat one (thing)”. Context usually disambiguates.

Is there a more explicit word in Icelandic for “alone” instead of using einn?

Yes, you can use aleinn / alein / aleitt, which more clearly means “alone” rather than the numeral “one”:

Ég borða aleinn. – I eat alone. (speaker masculine)
Ég borða alein. – I eat alone. (speaker feminine)

You can combine both emotional and physical aspects:

Stundum er ég einmana þegar ég borða aleinn.
– Sometimes I feel lonely when I eat alone.

Aleinn/ein/eitt is less ambiguous than einn/ein/eitt, because it can’t easily be interpreted as the number “one” in this position.

Why is the verb borða not changed here (no ending), while er is?

Icelandic distinguishes between:

Finite verb (conjugated for person/number, carries tense)
Infinitive or other non-finite forms

In this sentence:

er is the finite present tense of vera (to be), 1st person singular:
- ég er – I am
borða here is also finite present tense (not an infinitive), but its present form for ég happens to look like the infinitive:
- að borða – to eat (infinitive)
- ég borða – I eat
- þú borðar – you eat
- hann borðar – he eats

So borða is actually the conjugated 1st person singular present; it just shares the same form as the infinitive.

What does þegar mean here, and does the tense match English?

Þegar means “when” (introducing a time clause).

Both parts use present tense:

Stundum er ég einmana – Sometimes I am lonely
þegar ég borða einn – when I eat alone

Icelandic often uses the present tense in general/habitual statements where English also uses the present:

“Sometimes I am lonely when I eat alone.”

For specific past events, you’d switch to past tense in both clauses:

Stundum var ég einmana þegar ég borðaði einn.
– Sometimes I was lonely when I ate alone.

Why is there a comma before þegar in Icelandic?

Icelandic punctuation rules are a bit stricter about commas before subordinate clauses than modern English:

Subordinate clauses introduced by words like þegar, að, ef, vegna þess að etc. are usually preceded by a comma.

So:

Stundum er ég einmana, þegar ég borða einn.

In modern English, we might or might not put a comma:

Sometimes I’m lonely when I eat alone. (no comma also fine)

In Icelandic writing, including the comma before þegar is standard and expected.