§ 40. There are three Voices, Active, Middle, and Passive, generally distinguished by the termination.
The Middle is properly reflexive. Some of its tenses have an active meaning. A few verbs, called deponent, are throughout pass. in form, but act. or mid. in meaning.
§ 41. There are five Mood in each voice, the Indicative, Imperative, Subjunctive, Optative, and Infinitive, to which may be added the Participles; they are mostly known by means of the union-vowel--that which immediately precedes the termination.
§ 42. The Indic., Imper., Infin., and Participles correspond to the English, and have a short union-vowel, (ε, ο, or α,) except the Perf. and Pluperf. pass., which have no union-vowel; the Pluperf. act. and mid., which have ει; and the Aorists pass., which have η or its equivalent.
§ 43. The Imper. has but two persons. 2d and 3d. The Infin. has but one termination for all numbers and persons, and is very often used as a neut. noun, with the article, etc., yet retaining its construction as a verb.
§ 44. The Subj. and Opt. are used in certain dependent relations, like the English subjunctive and potential; the former has a long union-vowel, (η or ω,) and the latter a diphthong, (οι, αι, or ει.) The former generally represents an act as contingent upon outward circumstances, and the latter upon a will.
§ 45. The Tenses are nine, the Present, Imperfect, Perfect, Pluperfect, two Aorists, (1st and 2d, equivalent in sense,) and three Futures, (1st and 2d, equivalent to each other, and 3d, very rarely used;) they are distinguished by certain letters prefixed, inserted, or added to the stem or root of the verb. They represent time as compared with the present, and never date from that of a preceding verb.
§ 46. The Pres., Perf., Pluperf., and Fut. answer very nearly to the same tenses in English.
§ 47. The Imperf. denotes an act as going on, but incomplete or habitual at some time past: "was doing," etc.
§ 48. The Aorists indicate a single act at a definite time, (past in the Indic., but undetermined in the others moods.)
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