[Cf. Elpenor's The Greek Letters]
§ 3. Each word, except a very few monosyllables, has one of the following accents written over a vowel in it, which marks the place of the spoken tone. A few small words, called enclitics, generally throw their accent, as an acute, on the last syllable of the preceding word.
§ 4. The acute (´), which is the foundation of all the accents, stands on one of the last three syllables. In verbs, with the exception of certain forms, it stands as far toward the beginning of the word as the rules below allow. In other parts of speech it stands on the same syllable as in the ground-form, (that given in the lexicon,) except as required by these rules. When the last syllable has a long vowel or diphthong it stands on the syllable before the last.
§ 5. The grave accent (`) is only written in place of the acute on the last syllable when not before a pause, or when unemphatic. It is understood to belong to all other syllables.
§ 6. The circumflex (~) is placed on a syllable formed by the combination of two, the first of which had an acute and the second a grave; hence only on the last, or next to the last syllable, and only on a long vowel or a diphthong. When the last syllable has a short vowel, such a penult, if accented, takes the circumflex.
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