READ OUT LOUD. Choose which marked text you prefer to practice with - macrons in verse form, or macrons in prose order, or accent marks in prose order, or focusing on the meter. You will find materials for all of these options below. :-)
VERSE MACRONS. Here is the verse text with macrons (note short a in agrestis):
Altius in caenō plaustrum forte haesit agrestis;
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Segnis at Ālcīdēn precibus petit: "Ō! Deus," inquit,
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"Quid tibi nōbīscum?" Sīc torvus reddidit ille,
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Incute equīs flāgrum: propriā vī nītitor ipse;
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PROSE MACRONS. Here is the same text with macrons written out in prose word order:
Forte, Āgrestis plaustrum in caenō altius haesit; via imbre longō difficilis facta fuit. At Āgrestis segnis precibus Ālcīdēn petit; inquit: "Ō! Deus, dexter nōbīs adēs et auxilium refer." Sīc ille torvus reddidit: "Quid tibi nōbīscum? Quid opēs et auxilium ex aliīs rogās? Equīs flāgrum incute! Propriā vī tu ipse nītitor! Sī nōn prōfuerit, fās et adīre Deōs."
STRESS (ACCENT) MARKS. Here is the prose text with accents, plus some color-coding for the words of three or more syllables (blue: penultimate stress; red: antepenultimate stress):
Forte, Agréstis plaustrum in caeno áltius haesit; via imbre longo diffícilis facta fuit. At Agréstis segnis précibus Alcíden petit; inquit: "O! Deus, dexter nobis ades et auxílium refer." Sic ille torvus réddidit: "Quid tibi nobíscum? Quid opes et auxílium ex áliis rogas? Equis flagrum íncute! Própria vi tu ipse nítitor! Si non profúerit, fas et adíre Deos."
ELEGIAC COUPLET METER. Below I have used an interpunct dot · to indicate the metrical elements in each line, and a double line || to indicate the hemistichs of the pentameter line.
Altius· in cae·nō plau·strum for·t~ haesit a·grestis;
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Segnis a·t Ālcī·dēn preci·bus petit:· Ō! Deus,· inquit,
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Quid tibi· nōbīs·cum? Sīc· torvus· reddidit· ille,
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Incut~ e·quīs flā·grum: propri·ā vī· nītitor· ipse;
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IMAGE. Here's an illustration for the fable (image source) by Walter Crane:
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What follows is an unmarked version of the prose rendering to faciliate word searches:
Forte, Agrestis plaustrum in caeno altius haesit; via imbre longo difficilis facta fuit. At Agrestis segnis precibus Alciden petit; inquit: "O! Deus, dexter nobis ades et auxilium refer." Sic ille torvus reddidit: "Quid tibi nobiscum? Quid opes et auxilium ex aliis rogas? Equis flagrum incute! Propria vi tu ipse nititor! Si non profuerit, fas et adire Deos."