Learn Hardcore Icelandic: Ég er mjög þreyttur í kvöld.

Þreyttur is the masculine, singular, nominative form of the adjective þreyttur (tired).
The subject ég (I) doesn’t show gender itself, but the adjective agrees with the speaker’s gender.
- A man would say: Ég er mjög þreyttur í kvöld.
- A woman would say: Ég er mjög þreytt í kvöld.

So -ur here marks that the speaker is (grammatically) masculine.

How would the sentence change if the speaker is female?

Only the adjective changes; everything else stays the same:

Masculine speaker: Ég er mjög þreyttur í kvöld.
Feminine speaker: Ég er mjög þreytt í kvöld.

Here þreytt is the feminine (and also neuter) singular nominative form of the adjective.

If a group was speaking:

We (mixed group or all men): Við erum mjög þreyttir í kvöld.
We (all women): Við erum mjög þreyttar í kvöld.

What does í kvöld literally mean, and why is it translated as “tonight/this evening”?

Literally, í kvöld is:

í = in
kvöld = evening

So word-for-word it’s “in evening”.
However, in Icelandic this fixed phrase í kvöld is the normal way to say “this evening / tonight”, referring to the current upcoming evening of today.

Examples:

Ég fer í bíó í kvöld. – I’m going to the movies tonight.
Hittumst við í kvöld? – Shall we meet tonight?

So you should learn í kvöld as an idiomatic time expression meaning tonight / this evening, not just literally “in the evening” in general.

Why do we use í (“in”) with kvöld? Could we just say kvöld without í?

With time expressions like this, Icelandic often uses a preposition where English does not.

Í kvöld = tonight / this evening (specific: this evening)
Bare kvöld by itself is just the noun “evening” and doesn’t usually function like “tonight”.

You typically do not say:

✗ Ég er mjög þreyttur kvöld. (incorrect for “I am very tired tonight”)

You need the preposition:

Ég er mjög þreyttur í kvöld.

Compare with other time phrases:

í dag – today
í morgun – this morning
í gær – yesterday (this one is just an adverb, no preposition)

So í + time word is a common pattern, and í kvöld is the standard way to say “tonight”.

Why is the word order Ég er mjög þreyttur í kvöld and not something else? Where does mjög go?

The basic neutral order in Icelandic main clauses is:

Subject – Verb – (Adverb) – Complement

In this sentence:

Ég (subject)
er (verb)
mjög (adverb “very”)
þreyttur (adjective, complement)
í kvöld (time expression)

So mjög comes after the verb and before the adjective it modifies. That’s the most natural position.

You would normally not say:

✗ Ég er þreyttur mjög í kvöld. – This sounds poetic/weird.
✗ Ég mjög er þreyttur í kvöld. – Wrong word order.

So for “very tired” you want: er mjög þreyttur.

Can I move í kvöld to the beginning of the sentence?

Yes. To emphasize “tonight”, you can put í kvöld first:

Í kvöld er ég mjög þreyttur.

This is still correct Icelandic. The main change is in emphasis:

Ég er mjög þreyttur í kvöld. – Neutral: “I’m very tired tonight.”
Í kvöld er ég mjög þreyttur. – “Tonight, I’m very tired” (contrast with other times).

Icelandic allows more flexible word order than English, but the verb usually stays in second position in main clauses. When you move í kvöld to the front, the verb er becomes the second element: Í kvöld – er – ég – mjög þreyttur.

How would I negate this sentence? Where does ekki go?

The normal negated version is:

Ég er ekki mjög þreyttur í kvöld. – I’m not very tired tonight.

Word order:

Subject: Ég
Verb: er
Negation: ekki
Adverb: mjög
Adjective: þreyttur
Time phrase: í kvöld

So ekki comes right after the finite verb (er):

Ég er ekki mjög þreyttur í kvöld.

Why does er stay the same regardless of gender, while þreyttur/þreytt changes?

In Icelandic:

Verbs are conjugated for person and number (I/you/he/we/they), but not for gender.
Adjectives are declined for gender, number, and case.

So the verb vera (to be) in present tense:

ég er – I am
þú ert – you are
hann/hún/það er – he/she/it is
við erum – we are
þið eruð – you (pl.) are
þeir/þær/þau eru – they are

No gender changes for the verb.

The adjective, however, must match the (understood) gender of the subject:

Ég er þreyttur. (male)
Ég er þreytt. (female)

So er stays the same; þreyttur / þreytt changes.

How would I say “We are very tired tonight” using this pattern?

You mainly need to change the subject and adjust the adjective for number and gender.

Mixed group or all men:
- Við erum mjög þreyttir í kvöld.
- við = we
- erum = are (1st person plural)
- þreyttir = masculine plural (or mixed-gender plural) form
Group of only women:
- Við erum mjög þreyttar í kvöld.
- þreyttar = feminine plural form

The structure is exactly the same as in the original sentence; only the subject and the adjective ending change.

How do I pronounce Ég er mjög þreyttur í kvöld? Especially ég and þreyttur?

Approximate pronunciation (not strict IPA, but close enough for an English speaker):

Ég – often like “yei” or “yay”, starting with a y sound.
er – somewhat like English “air” but shorter.
mjög – like “myuhg”:
- m as in man
- j = y sound, like yes
- ö = rounded vowel, a bit like the u in burn (British), but with rounded lips
- final g is often weak or almost gone.
þreyttur:
- þ = voiceless th as in thing (never like this).
- rey – similar to English “ray” but shorter.
- tt – a strong, clear t sound, often with a little “stop”.
- ur – a short, reduced vowel with r, a bit like a very short “oor” or “ur”.
í kvöld:
- í – like a long ee in see.
- kv – like kv in kvetch, or k plus v.
- öld – roughly like “uhlt” with a dark l and a final t/d quality.

All stress is on the first syllable of each word: ÉG er MJÖG ÞREYTTur í KVÖLD.