Contract verbs are those verbs whose stem forms end in '''εω''' or '''αω''' or '''οω'''. When forming their various endings in conjugating, the ending undergoes changes.
===Basic Contraction Rulesfor Present and Imperfect Forms===
====εω====
===Further rules===
====Lengtheningfor Aorist and Future Forms====
Prior to adding the '''σ''' or '''θ''' in the Aorist or Future forms of an '''εω''' verb a lengthening occurs where ''εω'' is changed to ''η''
Prior to adding the '''σ''' or '''θ''' in the Aorist or Future forms of an '''οω''' verb a lengthening occurs where ''οω'' is changed to ''ω''
====Present Infinitive VerbsForms====
For the ''Present Infinitive'' form of contract verbs, the standard rules of contraction do not apply. For the ''Present Infinitive'' form the following changes occur: