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:
Nat canis; ōre gerit carnem, caro porrigit umbram.
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Spem carnis plūs carne cupit, plūs fēnore signum
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Nōn igitur dēbent prō vānīs certa relinquī.
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PROSE MACRONS. Here is the same text with macrons written out in prose word order:
Canis nat; ōre carnem gerit, caro umbram porrigit. Aquīs umbra cohaeret; canis hās aquās urget. Spem carnis plūs carne cupit, signum fēnoris plūs fēnore. Ōs aperit, sīc caro perit et spes. Certa igitur relinquī nōn dēbent prō vānīs. Sī quis sua nōn avet, ipse mox caret suīs.
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):
Canis nat; ore carnem gerit, caro umbram pórrigit. Aquis umbra cohaéret; canis has aquas urget. Spem carnis plus carne cupit, signum fénoris plus fénore. Os áperit, sic caro perit et spes. Certa ígitur relínqui non debent pro vanis. Si quis sua non avet, ipse mox caret suis.
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.
Nat canis·; ōre ge·rit car·nem, caro· porrigit· umbram.
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Spem car·nis plūs· carne cu·pit, plūs· fēnore· signum
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Nōn igi·tur dē·bent prō· vānīs· certa re·linquī.
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IMAGE. Here is an illustration for the story (image source) by Walter Crane:
What follows is an unmarked version of the prose rendering to faciliate word searches: Canis nat; ore carnem gerit, caro umbram porrigit. Aquis umbra cohaeret; canis has aquas urget. Spem carnis plus carne cupit, signum fenoris plus fenore. Os aperit, sic caro perit et spes. Certa igitur relinqui non debent pro vanis. Si quis sua non avet, ipse mox caret suis.