Lad paraplyen blive i skabet, hvis det ikke regner.

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Breakdown of Lad paraplyen blive i skabet, hvis det ikke regner.

• det: it
• hvis: if
• paraplyen: the umbrella

Questions & Answers about Lad paraplyen blive i skabet, hvis det ikke regner.

Why does the sentence start with Lad? What kind of verb form is it?

Lad is the imperative (command) form of the verb lade (to let / allow / have someone do something).
In instructions, Danish often uses Lad + object + infinitive to mean Let X do/remain... or more idiomatically Leave X...
So Lad paraplyen blive ... ≈ Leave the umbrella ...

Why is it paraplyen and not en paraply?

paraplyen is the definite form: the umbrella.

• en paraply = an umbrella (indefinite)
• paraplyen = the umbrella (definite)
  In a practical instruction, Danish commonly uses the definite when the umbrella is understood from context (e.g., your umbrella).

What is the function of blive here? Does it mean become?

blive can mean become, but it also commonly means remain / stay.
In Lad paraplyen blive i skabet, blive means remain: Leave the umbrella in the cupboard (i.e., let it stay there).

Why do we say Lad paraplyen blive... and not Lad paraplyen være...?