§ 60. Tenses expressing past time (Imperf. and Aorists Indic.) prefix ε ("syllabic augment") to the root; this coalesces with an initial vowel ("temporal augment") into the corresponding long vowel or diphthong. The Perf., Pluperf., and 3d Fut. not only do the same throughout the moods, but also prefix to the syllabic augment the initial consonant of the root ("reduplication") when this is a simple consonant or a mute followed by a liquid. The Pluperf. prefixes a second syllabic augment to the reduplication.
§ 61. Initial ρ, (which is doubled after the syllabic augment,) βλ, γλ, and γν, do not, except in a few cases, allow the reduplication. Verbs compounded with a preposition generally take the augment, etc., between it and the primitive. A few other irregularities occur.
§ 62. Verbs are classified in conjugation according to the radical letter following the root vowel, or diphthong, in the 1st pers. sing. Pres. Indic. act., lexicon form: in "liquid" verbs (not derivatives in άνω, which is merely strengthened for άω) this is a liquid; in "pure" verbs it is absent, so that the root appears to end in a vowel, etc. Very many verbs seem to be anomalous in some of their forms in consequence of deriving these from an obsolete kindred root. The lexicon gives most of these peculiarities.
§ 63. Liquid verbs almost always strengthen their root in the Pres. and Imperf.; they lengthen it in the 1st Aor. act. and mid. by changing the root vowel, if α into η, if ε into ει, while ι and ν merely become long. ε as a root vowel is generally changed into α in the 1st Aor. and 1st Fut. pass., the Perf. and Pluperf. act. and pass., and the 2d Aor. and 2d Fut. throughout, and again into ο in the Perf. and Pluperf. mid.
§ 64. The above strengthening in the Pres. and Imperf. consists in doubling λ, annexing ν to μ; or, in case of ν or ρ, in adding ι to a preceding α or ε, or lengthening ι or υ. The radical ν is often dropped in Perf. and Pluperf.
§ 65. Verbs with ε followed by a pi- or kappa-mute in the root frequently neglect to strengthen it in the Pres. and Imperf.; and verbs with ε in the root preceded by a liquid, usually change it into α and ο in the same tenses as liquid verbs, except in the 1st Aor. and Fut. pass.
§ 66. Pure verbs lengthen the root vowel before a tense characteristic, also in the Perf. and Pluperf. pass. A few occasionally neglect this, and some insert σ instead.
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