Breakdown of Wir müssen nicht umplanen, es sei denn, die Vorhersage ist falsch.
sein
to be
falsch
wrong
wir
we
nicht
not
Questions & Answers about Wir müssen nicht umplanen, es sei denn, die Vorhersage ist falsch.
Why doesn't es sei denn push the verb to the end in the second half of the sentence?
On its own, es sei denn functions like a coordinating conjunction (similar to und or aber). This means it connects two main clauses, so the verb ist stays in its normal second position in the clause: die Vorhersage ist falsch.
Could I use a subordinate clause structure here if I wanted to?
Yes! If you add dass after the comma, it becomes a subordinating conjunction. The sentence would then be: ... es sei denn, dass die Vorhersage falsch ist. Both versions mean the exact same thing and are very common in everyday German.
What does the phrase es sei denn literally mean?
It translates literally to 'it be then'. It is a frozen phrase built from the Konjunktiv I form of sein (sei), originating from an old phrasing like 'be it then that...'. You never need to conjugate it; it stays as a fixed expression meaning 'unless'.
Why is nicht placed right before umplanen?
In sentences with a modal verb like müssen, the negation nicht is placed immediately before the infinitive verb at the end of the clause when you are negating the entire action. Here, it negates the action of rescheduling (umplanen).