The Past Unreal Conditional
To talk about hypothetical past events—things that did not actually happen, like missing a flight or avoiding a traffic jam—we use the past unreal conditional.
The "if" clause (the condition) uses hvis followed by the past perfect tense (havde or var + the past participle).
The result clause often uses a past tense modal verb like ville (would) + have + the past participle.
Word order reminder: Because the hvis clause is a subordinate clause, adverbs like ikke come before the verb (ikke havde). If you start the sentence with the hvis clause, the result clause must invert its subject and verb to maintain the "verb second" (V2) rule.
| If I had not forgotten the boarding pass, I would not have missed the flight. | Hvis jeg ikke havde glemt boardingpasset, ville jeg ikke have misset flyet. |
Skipping "Ville"
In Danish, you don't always need ville have in the result clause. It is very common to simply use the past perfect tense again. The meaning remains exactly the same.
| If we had not been in the traffic jam, we would not have missed the flight. | Hvis vi ikke havde været i trafikproppen, havde vi ikke misset flyet. |
If the verb in either clause involves motion or a change of state (like rejst, gået, or ankommet), remember to use var instead of havde as your helper verb.
| If she had found the boarding pass, she would have gone to the security check. | Hvis hun havde fundet boardingpasset, var hun gået til sikkerhedskontrollen. |
Dropping "Hvis"
Just like in English, you can drop hvis. When you do, invert the subject and verb in the condition clause (e.g., "Had we heard..." instead of "If we had heard...").
| Had we heard the announcement in the terminal, we would have gone to the gate. | Havde vi hørt meddelelsen i terminalen, var vi gået til gaten. |
| Had they heard the announcement, they would have rebooked the flight ticket. | Havde de hørt meddelelsen, ville de have ombooket flybilletten. |
Changing the Clause Order
You can also put the result clause first. When the result clause starts the sentence, it takes normal word order, and there is no V2 inversion needed in the middle.
| We would not have missed the layover if the flight had not been delayed. | Vi ville ikke have misset mellemlandingen hvis flyet ikke havde været forsinket. |
| We would have rebooked the trip if we had known it. | Vi havde ombooket rejsen hvis vi havde vidst det. |