The Future Perfect
To talk about an action that will have been completed by a certain point in the future, Icelandic uses a compound construction: verða + búinn + að + infinitive.
Literally, this translates to "will be finished to [do something]".
Agreement of "búinn"
Because búinn functions as an adjective in this structure, its ending must change to match the gender and number of the subject.
For a masculine singular subject (like bakarinn or hann), use the base form búinn:
| The baker will have kneaded the dough early. | Bakarinn verður búinn að hnoða deigið snemma. |
| He will always have put the cinnamon rolls on the baking tray. | Hann verður alltaf búinn að setja snúðana á bökunarplötuna. |
For a feminine singular subject (hún), drop the final n to make it búin. For a neuter singular subject (það, deigið), it becomes búið:
| She will have kneaded the dough for the twisted doughnuts. | Hún verður búin að hnoða deigið fyrir kleinurnar. |
| The dough will have risen before the baking begins. | Deigið verður búið að hefast áður en baksturinn byrjar. |
When dealing with neuter plural or mixed-gender plural subjects (like þau or þið), the form is búin. Remember to also conjugate the auxiliary verb verða to match the subject (ég verð, þú verður, við verðum, þið verðið):
| You will have brushed everything before the baking. | Þið verðið búin að pensla allt fyrir baksturinn. |
Starting an Action (Fara að)
To express that an action is about to begin, you can use the phrase fara að + infinitive. While fara literally means "to go", in this context it translates to "to start to" or "going to" do something.
| We will start brushing the cinnamon rolls when the glaze is ready. | Við förum að pensla snúðana þegar glassúrinn er tilbúinn. |
| We sometimes start kneading inside the kitchen. | Við förum stundum að hnoða inni í eldhúsinu. |