Please make sure you read through Croy section 103. Here he provides a discussion of the formation of the perfect stem.
He notes that for vowel-initial verbs, the effects of reduplication are the same as augment. The initial vowel or diphthong becomes long as a result of reduplication.
For consonants that start with aspirated consonants, the aspiration is not reduplication. As a result, θ is reduplicated as τ-θ, φ is reduplicated as π-φ, χ is reduplicated as κ-χ.
There are also special rules regarding the reduplication of verbs that begin with two consonants, or with the letters that represent double consonants: ψ and ξ and ζ. These verbs reduplicate by adding an epsilon to the beginning of the stem, so that this also resembles augment.
Some perfect stems are created by suppletion, using the stem of an entirely different verb in order to provide the perfect stem. There are also other irregular forms found in the perfect system.
Because the perfect system is much less common than the present or aorist system, you should not worry about the odd or irregular forms in the perfect. Instead, make sure you can recognize the typical effects of reduplication, and that you are alert to the presence of a kappa in the perfect active forms. If you can watch for reduplication and for the presence of the kappa, you will be able to recognize most of the perfect forms that you run into in your reading.
Biblical Greek Online. Laura Gibbs, Ph.D. This work is licensed under a Creative Commons License. You must give the original author credit. You may not use this work for commercial purposes. If you alter, transform, or build upon this work, you may distribute the resulting work only under a license identical to this one. Page last updated: April 9, 2005 8:06 PM