The past subjunctive for strong verbs

Strong verbs build their past subjunctive (viðtengingarháttur þátíðar) from their past plural stem by applying an i-mutation (vowel shift).

The ó, á, and o → æ Shift

If the past plural contains ó, á, or o, the vowel shifts to æ. Append the standard subjunctive endings (-i, -ir, -i, -um, -uð, -u).

  • fara (past plural: fórum) → færi
  • taka (tókum) → tæki
  • sjá (sáum) → sæi
  • sofa (sváfum) → svæfi
  • koma (komum) → kæmi
  • vera (vorum) → væri
If the expedition took the sled, it would go faster.
Ef leiðangurinn tæki sleðann, færi hann hraðar.
The explorer would take the sled if the snow were deep.
Landkönnuðurinn tæki sleðann ef snjórinn væri djúpur.

The u → y Shift

If the past plural contains a u, it shifts to y.

  • finna (fundum) → fyndi
  • detta (duttum) → dytti
  • brjóta (brutum) → bryti
  • hlaupa (hlupum) → hlypi
If the explorer did not come with the sled, he would never find the supplies.
Ef landkönnuðurinn kæmi ekki með sleðanum, fyndi hann aldrei birgðirnar.
If the polar bear fell down into the crevasse, he would definitely be cold.
Ef ísbjörninn dytti ofan í sprunguna, væri honum örugglega kalt.

Hypotheticals with Þótt

Just like ef (if), the conjunction þótt (although / even if) sets up hypothetical scenarios and triggers the past subjunctive.

If a strong verb's past plural already has a front vowel (like the é in héldum, from the verb halda), the vowel does not mutate further. It simply takes the subjunctive endings (héldi).

The expedition would continue even if the storm broke the sled.
Leiðangurinn héldi áfram þótt stormurinn bryti sleðann.
Even if the storm were severe, the explorer would run away from the avalanche.
Þótt stormurinn væri slæmur, hlypi landkönnuðurinn burt frá snjóflóðinu.