Ég vil vaka lengur í kvöld.

Vil is the 1st person singular present tense of the verb að vilja (to want).

• Ég vil = I want
• The infinitive of the main action verb follows: vaka (to stay awake / to be awake).
• So the structure is: subject + vilja (conjugated) + infinitive
  → Ég vil vaka = I want to stay awake / I want to stay up.

Other forms of að vilja in the present tense, for comparison:

• Ég vil – I want
• Þú vilt – You (singular) want
• Hann/Hún/Það vill – He/She/It wants
• Við viljum – We want
• Þið viljið – You (plural) want
• Þeir/Þær/Þau vilja – They want

Both vaka and vakna are real verbs, but they mean different things:

• vaka = to be awake / to stay awake / to stay up
  
  • Ég vil vaka lengur = I want to stay awake longer.
• vakna = to wake up (change from sleeping to being awake)
  
  • Ég vil vakna fyrr = I want to wake up earlier.

In Ég vil vaka lengur í kvöld, the idea is “I want to stay up longer tonight”, so vaka is correct because you’re talking about remaining awake, not about waking up from sleep.

Lengur is the comparative form of the adverb lengi (for a long time).

• lengi = for a long time
• lengur = for a longer time / longer (in time)

So:

• Ég vil vaka lengi = I want to stay up for a long time.
• Ég vil vaka lengur = I want to stay up longer (than some reference point: than usual, than you, etc.).

This is different from langur, which is an adjective:

• langur (masc.), löng (fem.), langt (neut.) = long (in length or duration as an adjective)
  • langur dagur = a long day
  • löng bók = a long book

Summary:

• lengi – long (time), adverb
• lengur – longer (time), comparative adverb
• langur/löng/langt – long, adjective

Literally, í kvöld means in the evening:

• í = in
• kvöld = evening

But in Icelandic, í kvöld is the standard way to say this evening / tonight (the upcoming evening/nigth of today). It covers the same time range that English usually calls tonight.

Some related expressions:

• í gærkvöldi = last night / yesterday evening
• á morgun = tomorrow
• í gær = yesterday

So Ég vil vaka lengur í kvöld is naturally understood as I want to stay up later tonight rather than I want to stay up longer in the evening in a literal, stiff sense.

In Icelandic, when vilja (to want) is followed by a verb, that second verb goes directly in the infinitive without að:

• Ég vil fara – I want to go.
• Ég vil borða – I want to eat.
• Ég vil vaka – I want to stay awake.

Using að here (Ég vil að vaka) is ungrammatical.

Að is used in other kinds of subordinate clauses:

• Ég vil að þú komir = I want you to come.
  (Here að introduces a full clause with its own subject þú and verb komir.)

But when you just want want + to + verb for yourself, the pattern is:

subject + vilja (conjugated) + infinitive (no að)

The word order here is quite natural and typical:

• Ég (subject)
• vil (finite verb)
• vaka (infinitive verb)
• lengur (adverb)
• í kvöld (time expression / prepositional phrase)

So: [Subject] [Verb] [Infinitive] [Adverb] [Time phrase]

You have a little flexibility, but you must keep vil in the second position (Icelandic is a V2 language). Some acceptable variations:

• Ég vil vaka lengur í kvöld.
• Í kvöld vil ég vaka lengur. (emphasis on tonight)
• Ég vil í kvöld vaka lengur. (possible, but sounds more marked / less neutral)

Putting vil somewhere other than second position (in a main clause) would be wrong. Also, you normally keep lengur close to the verb it modifies (vaka).

The negation ekki goes right after the finite verb vil:

• Ég vil ekki vaka lengur í kvöld.
  = I don’t want to stay up longer tonight.

Pattern:

• Ég vil ekki [infinitive + other stuff].

More examples:

• Ég vil ekki fara. – I don’t want to go.
• Ég vil ekki borða núna. – I don’t want to eat now.

A rough guide (not IPA, just to help your ear):

• Ég – roughly like “yeg” or “yeh”, with a very short g that may be barely heard.
• vil – like “vil” in “village”, short i.
• vaka – “VAH-ka”, both a sounds are like the a in father.
• lengur – roughly “LENG-ur”:
  • e like English e in bed.
  • ng as in sing.
  • The final ur is short and reduced (almost like “ir” in “bird” for many English speakers, but very short).
• í – long ee sound, like “see”.
• kvöld – approximately “kvöld”:
  • ö is between English e and u; similar to the vowel in British “bird”, but rounded.
  • ld often sounds like a quick lt cluster in many Icelandic accents.

Stress is always on the first syllable of each word: ÉG vil VÁ-ka LENG-ur í KVÖLD (sentence-level intonation will soften this, of course).

In Icelandic, the verb að vilja takes a nominative subject, just like English:

• Ég vil = I want

Ég is the nominative form of I.

You only use mig (accusative) when the pronoun is an object:

• Hann sér mig. – He sees me.
• Þú þekkir mig. – You know me.

So in this sentence, you are the subject (the one who wants), so Ég is correct and Mig vil vaka… would be wrong.

Yes, you could say:

• Ég vil vera vakandi lengur í kvöld.
  Literally: I want to be awake longer tonight.

This is also grammatical and understandable. The difference is slight:

• vaka focuses on the action/state “to be awake / to stay awake / to stay up”.
• vera vakandi means “to be in the state of being awake”.

In most everyday contexts, vaka is shorter, more natural, and more common. Vera vakandi can sound slightly more descriptive or explicit, but both are fine.

Yes. Just like in English, Icelandic often uses the present tense to talk about near future when it’s about personal plans, intentions, or scheduled events:

• Ég vil vaka lengur í kvöld.
  = I want to stay up later tonight (future time).

Other examples:

• Ég fer í bíó á morgun. – I’m going to the cinema tomorrow.
• Við borðum hjá ömmu í kvöld. – We’re eating at grandma’s tonight.

There is no separate “will” auxiliary for this kind of future intention. Context (like í kvöld) makes the future meaning clear.

In time expressions like í kvöld, Icelandic typically uses the bare noun (no article), similar to English tonight rather than in the evening the.

• í kvöld – tonight / this evening
• í morgun – this morning
• í fyrra – last year

Í kvöldinu would sound strange in this meaning; it would suggest a specific, already-mentioned evening in some other context (and even then it’s not the usual phrasing for time).

So for the idiomatic tonight, you must say í kvöld, without an article.