indicative, imperative, subjunctive, optative.UPDATE: I highly recommend this Greek resource to anyone learning Greek.

Furthermore, a verb is conjugated according to its context, i.e. A verb may be in the active, middle, or passive voice, and is conjugated accordingly. The 'Aorist' tense denotes a simple, indefinite action, used when there is no need to indicate continuity, completion, or incompletion of the action denoted by the verb. The 'Perfect' tense denotes completed action. The 'Present' and 'Imperfect' tenses denote continuous or repeated action. A table of verbs is typically found at the end of most Greek textbooks: make sure to study it carefully. ευ as ef in 'left' or 'ev' in 'evolution' depending on the word.αυ as af in 'after' or 'av' in 'aviator', depending on the word.On the other hand, εϊ is pronounced 'e-ee' (ε ι)

On the other hand, αϊ is pronounced 'α-ee' (α ι) Diphthongs and examples of ¨ are as follows: The symbol is ¨ (διαλυτικά) and the second letter goes between the dots. There is a symbol for the separation of these letters to sound like individuals. Greek diphthongs (two letters that are pronounced as a single sound).So in Greek, putting random letters together can very well produce a pronounceable word, albeit it being a nonsensical word (just like above). In Greek language, there can be no wrong pronunciation if you know how to pronounce the individual letters correctly: each Greek letter has one and only one pronunciation, except for some limited combinations of letters which are paired (see below) and give a different pronunciation. Learn the Greek alphabet and the pronunciation of each letter. Take note that in the nonsensical word, you just put the correct sound of the letter (4th column) in its correct position in the nonsensical word and as a result you have the Greek pronunciation of that word. And a nonsensical, yet pronounceable word (random letters): βαγδεζηθικλαμενοξοπροστυφαχεψω (vaghthezeetheeklamenoksoprosteefachepso).