fljúga ("to fly") is a strong verb of Class 2, and it is the cleanest possible model for the feature that defines this class: a present-singular i-umlaut that fronts the stem vowel jú to ý. So "I fly" is flýg, not *fljúg — and yet "we fly" is fljúgum, with the diphthong restored. The verb is intransitive (you don't "fly" an object the way you do in English "fly a kite"; that needs a different construction), and it runs on the Class-2 vowel series jú – au – u – o: present flýg, preterite singular flaug, preterite plural flugu, supine flogið. That same series powers bjóða ("offer"), ljúga ("lie") and njóta ("enjoy"), so once you have fljúga in your ear you can conjugate the whole family.
Conjugation
Class: strong, Class 2 (the jú – au – u – o series). Auxiliary: hafa — ég hef flogið "I have flown." Transitivity: intransitive (no direct object); destination is expressed with a preposition (fljúga til + genitive, fljúga heim, fljúga yfir + accusative).
| Principal parts | |
|---|---|
| Infinitive | að fljúga |
| 1sg present | flýg |
| 1sg past | flaug |
| 3pl past | flugu |
| Supine | flogið |
| Person | Present (nútíð) | Past (þátíð) |
|---|---|---|
| ég | flýg | flaug |
| þú | flýgur | flaugst |
| hann / hún / það | flýgur | flaug |
| við | fljúgum | flugum |
| þið | fljúgið | fluguð |
| þeir / þær / þau | fljúga | flugu |
| Person | Present subjunctive | Past subjunctive |
|---|---|---|
| ég | fljúgi | flygi |
| þú | fljúgir | flygir |
| hann / hún / það | fljúgi | flygi |
| við | fljúgum | flygjum |
| þið | fljúgið | flyguð |
| þeir / þær / þau | fljúgi | flygju |
| Non-finite & imperative | |
|---|---|
| Imperative (þú) | fljúgðu! |
| Imperative (þið) | fljúgið! |
| Supine | flogið |
| Past participle (m/f/n) | floginn / flogin / flogið |
| Present participle | fljúgandi |
| Middle voice (miðmynd) | fljúgast á — "to come to blows, scuffle" (idiomatic) |
The present-singular i-umlaut: flýg, not fljúg
This is the feature to lock in first, because nothing else in the paradigm will make sense without it. In Class 2 the present singular fronts the stem vowel by i-umlaut — historically the present-singular ending contained an i, which pulled the back diphthong jú forward to ý. The plural endings had no such i, so the plural keeps jú untouched:
- Singular: ég flýg, þú flýgur, hann flýgur — fronted ý.
- Plural: við fljúgum, þið fljúgið, þeir fljúga — original jú.
So "I'm flying to Akureyri tomorrow" is ég flýg til Akureyrar á morgun, never \ég fljúg. The same split runs across the whole class: *bjóða → ég býð but við bjóðum; ljúga → ég lýg but við ljúgum; njóta → ég nýt but við njótum. Front the singular; let the plural keep the diphthong. English has nothing like this — our verb stem never changes between "I fly" and "we fly" — so the instinct to leave the vowel alone is exactly the instinct you have to override.
Ég flýg út til Kaupmannahafnar á fimmtudaginn.
I'm flying to Copenhagen on Thursday. Present singular 'flýg' (i-umlaut ý), with the directional 'út'.
Þessi flugvél flýgur beint til Boston, engin millilending.
This plane flies straight to Boston, no stopover. Present singular 'flýgur' (3sg, fronted ý).
Við fljúgum sjaldan — okkur finnst þægilegra að taka rútuna.
We rarely fly — we find it more comfortable to take the coach. Present plural 'fljúgum', keeps jú.
The past: flaug (sg.) vs flugu (pl.)
As with every strong verb, the preterite splits its vowel between singular and plural — au in the singular, short u in the plural. "The plane flew low over the city" needs the singular flaug (flugvélin flaug lágt); "the birds flew south" needs the plural flugu (fuglarnir flugu suður). The supine and participle drop to o: flogið, floginn. Don't let the singular au bleed into the plural or the supine — *flaugu and *flaugið are both wrong.
Vélin flaug inn í þokuna og hvarf sjónum okkar.
The plane flew into the fog and vanished from our sight. Past singular 'flaug' (au vowel).
Gæsirnar flugu yfir í þúsundatali í morgun.
The geese flew over by the thousand this morning. Past plural 'flugu' (short u).
Ég hef aldrei flogið á viðskiptafarrými.
I've never flown business class. Supine 'flogið' (o vowel) with auxiliary 'hef'.
fljúga til + genitive, and the intransitive pattern
fljúga is intransitive — it does not take a direct object. Where English says "fly a kite" or "fly a plane," Icelandic reaches for a different verb (láta flugdreka fljúga for the kite, fljúga of the pilot but stýra/fljúga vél in aviation register). For destinations, the idiomatic pattern is fljúga til + genitive of the place: fljúga til Íslands ("fly to Iceland"), fljúga til Reykjavíkur. Bare directionals work too: fljúga heim ("fly home"), fljúga burt ("fly away"). To fly over something is fljúga yfir + accusative.
Hvenær fljúgið þið til Íslands?
When are you flying to Iceland? 'fljúga til' + genitive 'Íslands'.
Fuglinn flaug yfir vatnið og settist hinum megin.
The bird flew over the lake and landed on the other side. 'fljúga yfir' + accusative 'vatnið'.
Common Mistakes
❌ Ég fljúg til London á morgun.
Incorrect — the present singular fronts the vowel: 'flýg', not '*fljúg'. The plain jú survives only in the plural (fljúgum).
✅ Ég flýg til London á morgun.
I'm flying to London tomorrow. Present singular 'flýg' (i-umlaut ý).
❌ Fuglarnir flaugu suður í haust.
Incorrect — the past PLURAL takes short u, not the singular au: it's 'flugu', not '*flaugu'.
✅ Fuglarnir flugu suður í haust.
The birds flew south in the autumn. Past plural 'flugu'.
❌ Ég hef flaugið mjög oft.
Incorrect — the supine has the o vowel: 'flogið', not '*flaugið' (that smuggles in the past-singular au).
✅ Ég hef flogið mjög oft.
I've flown very often. Supine 'flogið' (o).
❌ Hún flýgaði heim eftir ráðstefnuna.
Incorrect — 'fljúga' is strong, not weak; there is no '-aði'. The past singular is the ablaut form 'flaug'.
✅ Hún flaug heim eftir ráðstefnuna.
She flew home after the conference. Past singular 'flaug'.
❌ Við fljúgum til Ísland í sumar.
Incorrect — 'fljúga til' governs the GENITIVE: 'Íslands', not the nominative 'Ísland'.
✅ Við fljúgum til Íslands í sumar.
We're flying to Iceland this summer. 'til' + genitive 'Íslands'.
Key Takeaways
- flýg / flýgur (present sg., i-umlaut ý), fljúgum / fljúgið / fljúga (present pl., keeps jú); past flaug (sg.) / flugu (pl.); supine flogið; participle floginn.
- The class series is jú – au – u – o, shared with bjóða, ljúga, njóta — one pattern, four verbs.
- The present singular fronts the vowel: ég flýg, never \ég fljúg*. The plural keeps the diphthong.
- fljúga is intransitive; destinations take prepositions — fljúga til
- genitive (til Íslands), fljúga heim, fljúga yfir
- accusative.
- genitive (til Íslands), fljúga heim, fljúga yfir
- Auxiliary is hafa (ég hef flogið); the imperative is fljúgðu.
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