"Vorbereiten" and its past participle form

Question

Is there a particular grammatical rule for the form of the past participle of vorbereiten?
I mean, vorbereiten is a separable verb, so it would be sensible to have, let's say, "Er hat vorgebereitet", but the correct form is "Er hat vorbereitet". Am I missing something?

Let's take two separable verbs, durchführen and vorbereiten:

• In the first case, we have, e.g., "Sie hat Aufträge durchgeführt".

• In the second case, we have, e.g., "Sie hat Besprechungen vorbereitet".

Could you tell me why there's no ge in the second case?

Answer 1

The "Perfekt" is built as followed:

"Hilfsverb" + Nomen + Partizip 2

So we have to focus on the "Partizip 2" In German normally the "Partizip 2" is built as followed:

Weak Verbs/Mixed Verbs:

"ge" + Verbstamm + "t"/"et"/"en" ...

Strong Verbs:

"ge" + Perfektstamm + "en"

There are some verbs which build the "Partizip 2" without the "ge":

• die untrennbaren Verben mit den Präfixen er-, ver-, zer-, be-, ge-, ent-, emp-, hinter-
• Verben auf -ieren
• trennbare Verben, die mit einem Verb aus Punkt 1&2 gebildet wurden
• die Verben mit den Präfixen über-, unter-, um-, durch-, wider-, wenn sie unbetont und untrennbar sind

Your verb "vorbereiten" is included in the 3rd Point, its separable, but mixed with "be" and that's the reason why you don't write it with "ge". Other examples for this rule would be:

• abbezahlt
• überreagiert

Answer 2

It seems that you refer to a rule that the past participle of a separable verb prefix+base is prefix+participle of base (e.g. umhören -> umgehört), while in the Inseparable case the ge- of the participle of the base is dropped (e.g. verhören -> verhört). In this case however, the participle of bereiten has no ge- to begin with, it is bereitet. So the participle vorbereitet still follows that rule if it is properly formulated.

As to why the participle of bereiten is not * gebereitet, I assume that it is treated as an insepearable verb itself, even though I think that this is etymologically not fully correct.