Learn Hardcore Danish: Hvis jeg glemmer nøglen, må jeg ringe til min søster. - If I forget the key, I must call my sister.

Danish main clauses follow the V2 rule: the finite verb must be in second position. The fronted clause Hvis jeg glemmer nøglen counts as the first element, so the finite verb må comes before the subject: må jeg ringe …. Without anything fronted, you would have the default order: Jeg må ringe …. The subordinate clause itself keeps normal order: jeg glemmer, not glemmer jeg.

What’s the difference between hvis and når?

hvis = if (hypothetical or uncertain condition): Hvis jeg glemmer nøglen …
når = when/whenever (something expected or habitual): Når jeg glemmer nøglen, ringer jeg til min søster. Using hvis here signals it’s only a possibility, not a certainty.

Does må mean “may” (permission) or “must/have to” (necessity) here?

Both meanings exist, and the sentence is ambiguous without context. In everyday Danish, må often means “have to/need to” (practical necessity): “If I forget the key, I’ll have to call my sister.” It can also mean “may” (permission), but that usually needs clarifying context.

If I want to be unambiguously about obligation, what should I use instead of må?

Strong or rule-like obligation: skal — “Hvis jeg glemmer nøglen, skal jeg ringe …” (sounds like a rule or plan).
Practical necessity: er nødt til at — “Hvis jeg glemmer nøglen, er jeg nødt til at ringe …” (clearly “have to,” no permission reading).

Why is it ringe til my sister and not just ringe my sister?

With a person as the object, Danish uses the preposition til: ringe til nogen (“call someone”). You can also say ringe nogen op (“call someone up”): Jeg ringer hende op. But ringe nogen without til or op is not standard. Note: ringe efter means “call for” (e.g., ringe efter en taxa).

Why is it nøglen (the key) and not en nøgle (a key) or min nøgle (my key)?

nøglen (definite suffix -en) indicates a specific, known key (e.g., the house key).
en nøgle is non-specific (“a key”).
min nøgle stresses whose key it is. If ownership matters, use min nøgle. Important: With a possessive you don’t add the definite suffix, so say min nøgle, not min nøglen.

Is the comma after the hvis-clause required?

After a fronted subordinate clause, the comma is optional in modern Danish punctuation. Both are accepted:

Hvis jeg glemmer nøglen, må jeg …
Hvis jeg glemmer nøglen må jeg … Most writers keep the comma; it’s never wrong to include it.

Why is glemmer in the present tense when this is about the future?

Danish typically uses the present tense for future time in conditionals: Hvis jeg glemmer … English does the same in if-clauses. You can mark futurity in the main clause if needed (e.g., vil jeg ringe = I will call), or add adverbs like i morgen. Don’t use vil in the if-clause to mean future.

Why is the order jeg glemmer in the hvis-clause and not glemmer jeg?

Subordinate clauses (introduced by hvis, at, fordi, etc.) do not use main-clause V2 inversion. They keep subject-verb order: jeg glemmer. Inversion (glemmer jeg) would signal a main-clause question or a V2 main clause, not a subordinate clause.

How do I make this negative? Where does ikke go?

Place ikke after the finite verb. With a modal like må, it goes right after the modal:

Prohibition: Hvis jeg glemmer nøglen, må jeg ikke ringe til min søster. = I’m not allowed to call.
Lack of necessity uses a different verb: behøver ikke — Hvis jeg glemmer nøglen, behøver jeg ikke at ringe … = I don’t need to call.

Can I add så in the main clause?

Yes. It’s common and perfectly natural, especially in speech: Hvis jeg glemmer nøglen, så må jeg ringe til min søster. It’s like English “then.”

Could I say something like “If I end up forgetting the key …” in Danish?

Yes: Hvis jeg kommer til at glemme nøglen, … (neutral “end up/accidentally”). You can also say Hvis jeg skulle glemme nøglen, …, which makes the scenario sound more tentative.

Pronunciation tips for tricky words like jeg, må, nøglen, ringe, søster?

jeg ≈ “yai” (IPA roughly [jɑj]); very commonly reduced in fast speech.
må ≈ “maw/moh,” long vowel (IPA [mɔː]).
nøglen ≈ “NUR-lehn,” with the rounded front vowel [œ]; the g works like a y-sound: [ˈnœjlən].
ringe ≈ “RING-eh,” with ng as
søster ≈ “SUST-er,” with rounded ø: [ˈsøsdɐ] (the final r is weak in many accents).

Can I drop the second jeg to avoid repetition?

No. Danish is not a pro-drop language; you must include the subject: … må jeg ringe …, not … må ringe ….