Learn Hardcore German: Die Klinik verschiebt alle Termine, wenn die Anzahl der Ärzte nicht ausreicht. - The clinic postpones all appointments when the number of doctors is not sufficient.

In German main clauses the finite verb always occupies the second position (V2 rule).
– Here Die Klinik is position 1.
– verschiebt (the finite verb) is position 2.
– The rest of the clause follows.
This is different from English, where the verb usually comes immediately after the subject.

Why is alle Termine in the accusative plural and not “alle die Termine”?

Termine is the direct object of verschieben, so it takes the accusative case.
Since alle already marks “all” in the plural, you don’t need the definite article die again.
Saying “alle Termine” is the natural way to express “all appointments.”

Why does the verb ausreicht appear at the very end of the clause?

The clause starting with wenn is a subordinate (dependent) clause, and in German subordinate clauses the finite verb moves to the end (verb‐final rule).
So ausreicht comes last in wenn die Anzahl der Ärzte nicht ausreicht.

Could we use falls instead of wenn, and would the meaning change?

Yes, you can often use falls (‘in case’) interchangeably with wenn (‘if’) in conditional sentences.
– wenn focuses on a general condition (“whenever/if”).
– falls often implies a more hypothetical or less likely scenario.
In your sentence both are acceptable:
“Die Klinik verschiebt alle Termine, falls die Anzahl der Ärzte nicht ausreicht.”

Why is Anzahl singular but Ärzte plural, and why is there no article before Ärzte?

Anzahl (‘number’ or ‘quantity’) is a singular noun. It takes a singular verb (reicht).
Ärzte (‘doctors’) is what you’re counting, so it’s in the genitive plural to show possession/quantity: der Ärzte.
In the genitive you don’t need an extra article before Ärzte; der already marks the genitive for Anzahl.

Why not say “wenn die Ärzte nicht reichen” instead of “wenn die Anzahl der Ärzte nicht ausreicht”?

You could say “wenn die Ärzte nicht reichen”, but it sounds less precise.
– reicht normally means “is enough.”
– Saying “die Ärzte reichen nicht” is understandable but a bit colloquial.
Using “die Anzahl der Ärzte reicht nicht aus” is more formal and explicitly mentions the “number” not being sufficient.

Why is there a comma before wenn? Do all clauses starting with wenn need a comma?

Yes. In German, a comma is mandatory before any subordinate clause, including those introduced by wenn.
So you write:
“Die Klinik verschiebt alle Termine, wenn …”
If the wenn-clause comes first, you also set off the main clause with a comma.

What does verschieben exactly mean here? Can it mean both “postpone” and “reschedule”?

verschieben can cover both senses:

To postpone (delay to a later date):
– “den Termin um eine Woche verschieben” → shift it by one week.
To reschedule (move to a different time):
– “den Termin auf nächste Woche verschieben.”
Context tells you whether it’s an outright delay or simply choosing a new slot.