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:
Et pedibus segnis, tumidā et prōpendulus alvō,
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Mordicus ipse sibī medicāta virīlia vellit,
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Hūius ab exemplō discās nōn parcere rēbus,
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PROSE MACRONS. Here is the same text with macrons written out in prose word order:
Fiber, et pedibus segnis et alvō tumidā prōpendulus, īnsidiās tamen hāc arte effugit: mordicus ipse medicāta virīlia sibī vellit, atque abicit, gnārus sēsē ob illa petī. Ab hūius exemplō discās rēbus nōn parcere, et hostibus aera dare, ut vītam redimās.
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):
Fiber, et pédibus segnis et alvo túmida propéndulus, insídias tamen hac arte éffugit: mórdicus ipse medicáta virília sibi vellit, atque ábicit, gnarus sese ob illa peti. Ab huius exémplo discas rebus non párcere, et hóstibus aera dare, ut vitam rédimas.
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.
Et pedi·bus seg·nis, tumi·d~ et prō·pendulus· alvō,
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Mordicus· ipse si·bī medi·cāta vi·rīlia· vellit,
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Hūius a·b exem·plō dis·cās nōn· parcere· rēbus,
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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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What follows is an unmarked version of the prose rendering to faciliate word searches:
Fiber, et pedibus segnis et alvo tumida propendulus, insidias tamen hac arte effugit: mordicus ipse medicata virilia sibi vellit, atque abicit, gnarus sese ob illa peti. Ab huius exemplo discas rebus non parcere, et hostibus aera dare, ut vitam redimas.