Learn Hardcore Norwegian: Alle hører fløyten når dommeren blåser. - Everyone hears the whistle when the referee blows.

In this sentence we talk about a specific whistle—the referee’s. Norwegian marks definiteness by adding a suffix to the noun rather than using a separate article.
• fløyte = “a whistle” (indefinite)
• fløyten = “the whistle” (definite)
So Alle hører fløyten literally means “Everyone hears the whistle.” Saying en fløyte would mean “a whistle,” which changes the nuance to any whistle rather than the referee’s.

What is the gender of fløyte, and why can its definite form be fløyten or fløyta?

In Bokmål, fløyte is a common‐gender noun (historically feminine). Common‐gender nouns can take either the masculine‐style ending -en or the feminine‐style ending -a in the definite singular.
• fløyten = definite with masculine‐style suffix
• fløyta = definite with feminine‐style suffix
Both are correct, though fløyten is more widespread in everyday Bokmål speech.

Why is dommeren in its definite form? Shouldn’t it be just dommer?

We refer to a specific person—the referee in the game—so we use the definite form.
• dommer = “a referee” (indefinite)
• dommeren = “the referee” (definite)
Using dommeren makes it clear we mean that particular referee who’s about to blow the whistle.

Why is there no preposition before fløyten? In English we’d say listen to the whistle.

Norwegian høre is a transitive verb that takes its object directly, so you say høre fløyten (“hear the whistle”) with no preposition. If you want to express “listen to the whistle” (actively pay attention), you use høre på fløyten, where på is the required preposition.

What is the infinitive of blåser, and how is this verb conjugated?

The verb is å blåse (“to blow”). Its basic conjugation is:
• Present: blåser
• Past: blåste
• Perfect: har blåst
So dommeren blåser = “the referee blows,” dommeren blåste = “the referee blew,” etc.

Why is the word order in når dommeren blåser subject–verb and not inverted like in main clauses?

After a subordinating conjunction such as når (“when”), Norwegian uses the standard Subject-Verb-Object (SVO) order inside that subordinate clause. Verb–subject inversion (V2) happens in main clauses (statements and questions), not in subordinate clauses. Hence når dommeren blåser, not når blåser dommeren.

Could we use da instead of når here? What’s the difference?

da is generally used for a single, specific moment or event in the past (“when I arrived, he left”). når is used for:
• Repeated or habitual events (“when the referee blows the whistle, everyone hears it”)
• Future situations (“when it rains tomorrow…”)
Since this sentence describes what happens whenever the referee blows, når is correct.

What’s the difference between høre and lytte? Can we say alle lytter til fløyten?

• høre = “to hear” (passively perceive a sound)
• lytte (til) = “to listen (to)” (actively focus on a sound)
You can indeed say Alle lytter til fløyten to emphasize that everyone is paying attention to the whistle, but Alle hører fløyten simply states that everybody hears it.