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: iis scans as one syllable):
Anguillās quisquis captat, sī limpida verrat
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Cassus erit, lūdetque operam: multum excitet ergō
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Dīves erit: sīc iīs rēs pūblica turbida lūcrō est,
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PROSE MACRONS. Here is the same text with macrons written out in prose word order:
Quisquis anguillās captat, sī flūmina limpida verrat , sī lacūs illīmēs adīre ausit, cassus erit et operam lūdet: sī ergō crētae multum excitet et palmula aquās vitreās turbet, dīves erit. Sīc rēs pūblica turbida lūcrō est iīs, quī pāce ēsuriunt, lēgibus arctātī.
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):
Quisquis anguíllas captat, si flúmina límpida verrat , si lacus illímes adíre ausit, cassus erit et óperam ludet: si ergo cretae multum éxcitet et pálmula aquas vítreas turbet, dives erit. Sic res pública túrbida lucro est iis, qui pace esúriunt, légibus arctáti.
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.
Anguil·lās quis·quis cap·tat, sī· limpida· verrat
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Cassus e·rit, lū·detqu~ ope·ram: mul·t~ excitet· ergō
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Dīves e·rit: sīc· iīs rēs· pūblica· turbida· lūcr~ est,
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IMAGE. Here's an illustration for the fable (image source) from a 1621 edition of the emblems:
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Here is another illustration from the Medici Aesop, which is online at the New York Public Library website.
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What follows is an unmarked version of the prose rendering to faciliate word searches: Quisquis anguillas captat, si flumina limpida verrat , si lacus illimes adire ausit, cassus erit et operam ludet: si ergo cretae multum excitet et palmula aquas vitreas turbet, dives erit. Sic res publica turbida lucro est iis, qui pace esuriunt, legibus arctati.