Ancient Greek verbs

Ancient Greek verbs have four moods (indicative, imperative, subjunctive and optative), three voices (active, middle and passive), as well as three persons (first, second and third) and three numbers (singular, dual and plural).

In the indicative mood there are seven tenses: present, imperfect, future, aorist (the equivalent of past simple), perfect, pluperfect, and future perfect. (The last two, especially the future perfect, are rarely used). In the subjunctive and imperative mood, however, there are only three tenses (present, aorist, and perfect). The optative mood, infinitives and participles are found in four tenses (present, aorist, perfect, and future) and all three voices. The distinction of the "tenses" in moods other than the indicative is predominantly one of aspect rather than time.

The different persons of a Greek verb are shown by changing the verb-endings; for example λύω (lúō) "I free", λύεις (lúeis) "you free", λύει (lúei) "he or she frees", etc. There are three persons in the singular ("I", "you (singular)", "he, she, it"), and three in the plural ("we", "you (plural)", "they"). In addition there are endings for the 2nd and 3rd persons dual ("you two", "they both"), but these are only very rarely used.

A distinction is traditionally made between the so-called athematic verbs (also called mi-verbs), with endings affixed directly to the root, and the thematic class of verbs which present a "thematic" vowel /o/ or /e/ before the ending. The endings are classified into primary (those used in the present, future, perfect and future perfect of the indicative, as well as in the subjunctive) and secondary (used in the aorist, imperfect, and pluperfect of the indicative, as well as in the optative).

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