The Middle Voice Supine
When describing a process that has occurred over time—such as fermentation or brewing—we use the auxiliary verb hafa (to have) followed by the supine (sagnbót).
For many middle voice verbs (verbs ending in -st), forming the supine is incredibly easy: it looks exactly identical to the infinitive form. The standard -ð ending that you would see in the active voice's supine simply disappears before the -st suffix.
| Has the brew fermented well in the container? | Hefur bruggið gerjast vel í ílátinu? |
| The brew has fermented and the carbonation has formed. | Bruggið hefur gerjast og kolsýran hefur myndast. |
Vowel Dropping in Weak Verbs
For other regular middle voice verbs, the -a- found before the -st in the infinitive drops out in the supine. For example, að fyllast (to fill up) becomes fyllst, and að dreifast (to spread) becomes dreifst.
| The container has filled up with both carbonation and a lot of foam. | Ílátið hefur fyllst bæði af kolsýru og mikilli froðu. |
| It is easy to see that the foam has spread well through the brew. | Það er auðséð að froðan hefur dreifst vel um bruggið. |
Strong Verbs
Strong middle voice verbs change their stems entirely, much like their active counterparts. The highly common verb að setjast (to settle or sit down) takes the short supine form sest.
| The sediment has settled on the bottom and the drink is beautiful. | Botnfallið hefur sest á botninn og drykkurinn er fallegur. |
| Finally, the brew has matured and the sediment has settled. | Loksins hefur bruggið þroskast og botnfallið sest. |